The Low Carbohydrate Handbook
Low Carb Wiki Editorial
- Author: Sizzlechest
- Source: Sizzlechest Original
- Topic: A breakdown of all the basic facts of low-carb, and some more advanced information. Intended to introduce newcomers to the core concepts.
What is low carb dieting?
The term is very broadly applied to a range of diets that require some form of carbohydrate restriction. Some diets limit the amount of overall carbohydrate, while others focus on certain types of foods, generally ones high in starch and sugars. (Since starch turns to sugar in our bodies, many diet writers do not make a distinction between the two.) Still others focus on how glycemic the diet is. Generally, any diet whose primary focus is the reduction of carbohydrate in any way is what is meant by “low carb.” Some examples would be Atkins, South Beach, Zone, Protein Power, Sugar Busters, Carbohydrate Addicts Diet, etc.
The American Diabetes Association defines low-carbohydrate diets as less than 130g per day or 26% of a 2,000-calorie diet. However, their focus is more on managing diabetes than weight loss.
A number of scientists, nutritionists, and other experts who have been involved with low carb dieting got together in 2008 and, for the first time ever, defined what constitutes a low carb diet. Here’s what they came up with:
- Low-carb ketogenic diet (LCKD): less than 50g carbs and 10% calories daily.
- Low-carb diet (LCD): 50-130g carbs daily and between 10-26% of calories.
- Moderate-carb diet (MCD): 130-225g carbs daily and between 26-45% of calories.
For the purpose of consistency in this thread, I will define a low carb diet as one that contains less than 50g carbs and 10% calories per day. This is basically an Atkins “Ongoing Weight Loss” (i.e., maintenance) diet and is usually the level where carb reduction introduces statistically significant advantages compared to other diet plans.
It’s also implied that a low carb diet is high in fat.* This isn’t a bad thing as I will explain shortly.
*Realistically, the percentage of fat calories is what increases rather than the actual amount of fat consumed.
Why is restricting carbs important to dieting?
From the article, Good Calories, Bad Calories: What Really Makes Us Fat? by Gary Taubes:
“As it turns out, every hormone in our body works to release fat from our fat tissue, with the singular exception of insulin, which works to put it there. [He neglected ASP -Sizzlechest] And insulin levels in our blood are determined primarily by the carbohydrate content of our diet. The more carbohydrates we consume, and the easier they are to digest, the higher our insulin. Insulin tells our fat tissue to accumulate fat. So long as insulin levels remain elevated, fat is locked in the fat tissue and can’t escape.”
“After a meal is digested, insulin levels should decline. When this happens, fat is released from the fat tissue in the form of fatty acids and these are then burned in cells for fuel. For this reason, another necessary requirement for remaining lean is to have lengthy periods during which insulin levels are low and we burn our fat for fuel. When insulin levels remain elevated, fat can’t escape from the fat tissue. It goes in, but it doesn’t come out, and we can’t use it for energy. A meal without carbohydrates is a meal that doesn’t stimulate any significant insulin secretion. You store very few, if any, calories as fat, and you get plenty of opportunity to burn the fat you had stored.”
Here are two excerpts from the documentary “Fat Head” by Tom Naughton that provide a visual explanation:
A great semi-technical in-depth explanation of how insulin affects fat storage is provided here: Research on Obesity Targets Insulin.
How do I count carbs?
Digestible carbohydrates are broken down into simple sugars like glucose, maltose, galactose, fructose*, etc. Non-digestible carbohydrates, like fiber, are not absorbed and have no impact on your blood-sugar levels.
People sometimes talk about the healthiness of “complex carbohydrates” vs.“simple carbohydrates” like refined sugars. (These are sometimes billed as the “good” vs.“bad” carbohydrates.) Complex carbohydrates are chains of three or more single sugar molecules linked together. Long chains of sugar molecules are called starches. Starches are easily broken down by the digestive system, starting with saliva. No matter how long the chain, all starches break down into glucose. That whole-wheat bread and potato you ate that’s full of starch? They all end up as the same thing: sugar.
To calculate the net, or effective, carbohydrate content of a food, subtract the number of grams of fiber from the number of grams of carbohydrate. For example, 1 cup of blackberries has 14 grams of carbs, but almost 8 grams of it comes from fiber. Total Carbs – Fiber = Net Carbohydrate or in our example, 14 grams – 8 grams = 6 grams of net carbs.
Sometimes you’ll run into something called “sugar alcohol” listed under the carbohydrate section. It seems that only a subset of the population metabolizes sugar alcohols as sugar. It is quite possible that some people lack some enzyme(s) needed to digest them and turn them into blood sugar. Since those people’s bodies can’t turn these sugar alcohols into glucose, they do not experience a blood sugar rise when they eat them. Beware of foods containing sweeteners like maltitol since it is effectively has the same impact as glucose. The only sugar alcohol that has absolutely no insulin response is mannitol and erythritol. There are many other sugar alcohols, but I can’t tell you how to count their carbs with great certainty since the insulin response varies from person to person. A list of sugar alcohols and their Glycemic Index can be found Here and Here (I’ll explain more about the Glycemic Index later.)
The US labeling laws allow products that contain >0 and <0.5 carbs to be labeled as 0 carbs and products with >0.5 to <1 carbs to be labeled as less than 1 carb. However, carbohydrate labeling is not strictly regulated. Manufacturers can round up or round down the carb grams listed in the nutritional info. I’m not suggesting you sperg out about the rounding issues, but you should be aware it’s happening.
*Fructose does not cause an insulin response, but has some nasty long term side effects. In particular, insulin resistance. Fructose is digested in the liver and converted into triglycerides (“bad” cholesterol). That’s right; high carb diets raise your cholesterol.
From Jenny's Low Carb Facts and Figures:
"In many European countries, fiber is already deducted from the label’s total carb count. For example, imported Scandinavian bran crackers that list 3 grams of carbohydrate and 3 grams of fiber do not contain zero grams of carbohydrate. If they followed U.S. labeling conventions, their labels would show 6 grams of carbohydrate and 3 grams of fiber, since the European labels have already deducted the fiber from the total. This is also true of many imported chocolates."
"To make it even more confusing, an increasing number of U.S. labels also deduct fiber from total counts, too. Many nuts do this, but so do premium chocolates. For example, despite fact that most labels for walnuts usually list “3 grams total carbohydrate, 3 grams fiber” walnuts are not a zero carb treat! They contain about 2 grams of carbohydrate per ounce."
You also need to check if sugar alcohols are counted. Atkins products don’t count them in their net carb counts, but they do include them in the total carbs. If you’re unsure about the nutritional label, you can use this Hidden Carbs Calculator to ease your mind.
What about calories?
Generally, low carb diets don’t require you to keep track of caloric intake. A calorie is the energy needed to raise the temperature of one kilogram of water one degree Celsius. Your body does not literally burn foods like a calorimeter. Different macronutrients (i.e., carbohydrate, fat, and protein) have different effects on hormones, which have different effects on fat storage, and provide different amounts of energy to the body in different ways.
You’ve probably been told weight loss is a simple matter of calories in minus calories out. This was “proven” by citing the First Law of Thermodynamics. You were told wrong. The First Law of Thermodynamics has to do with energy balance in a CLOSED system. Your body is not a closed system, unless you figured out a way to not poop, breathe, sweat, etc. In fact, calories from macronutrients CAN’T be equal since a deficiency of carbs requires your body to convert protein into glucose. That process has a “cost.” To say calories are all equal violates the Second Law of Thermodynamics.
In short, using the word “calorie” to connote the amount food consumed or amount of energy ingested is clumsy and inaccurate. However, it’s a term used throughout nutritional literature, so we’re stuck with it. Calorie counts can be useful “rules of thumb,” but always keep in mind their limitations.
Experiments have been conducted prove people respond differently to the food they consume. Either the scientists found a way to violate the laws of thermodynamics, or most people’s understanding of how the body uses food is wrong. Guess which one it is? One famous study was conducted in the Vermont state prison where every inmate was forced to eat the same amount without exercising. The amount of weight gained varied greatly.
Fredrik Nyström conducted a controlled experiment at Linköping University to determine the effects of an extreme high calorie diet on people who are naturally thin. He force fed the participants 6,000 calories a day, roughly double what most of the volunteers ingested normally. He discovered that their weight gains were neither predictable nor consistent within the group. After the experiment concluded, the test subjects quickly returned to their pre-test weights and eating habits.
The BBC documentary Horizon aired a documentary called Why Are Thin People Not Fat that featured a repeated experiment in England conducted by Nyström with the same results. I found a copy of it on YouTube:
Part 1 - Part 2 - Part 3 - Part 4 - Part 5 - Part 6 - Part 7
Claiming obesity is a product of a positive energy balance is as enlightening as saying global warming is a product of the Earth getting hotter. No sh*t, Sherlock. It’s not very helpful to state the effect while ignoring the cause. We must determine how the body is processing the energy we ingest, and how it can be prevented from turning into fat. That’s where hormones come in since hormones regulate fat storage. If we can manipulate our hormones, we can change how our bodies use the calories we eat. An overweight person is not necessarily someone who overeats; their body simply may be storing an undesirable amount of fuel as fat instead of using it for energy. Likewise, a naturally skinny person may be converting their surplus fuel into energy, lean tissue growth, or heat instead of fat.
What if we restrict calories a whole lot? Won’t that cause weight loss? Yes! If someone is starved of fuel, the body is forced to use those restricted calories to preserve survival. That may mean using fat stores, breaking down lean muscle tissue, lowering body temperature, lethargy, etc. Of course, this is not a desirable long term condition. The beauty of low carb diets is that they do not attempt to starve the body of energy. They attack the root of the problem: fat metabolism.
Some studies attempt to show that all diets have the same effective weight loss when strictly controlling calories. Participants are separated into different groups, each with a different predefined ratio of fat, protein, and carbs. The kinds of foods eaten by each group can differ greatly. However, the total number of calories ingested each day for each group is must be the same. The term for this kind of comparison is “isocaloric.” The “cheat” they use in these studies is that they do not allow the participants to ingest their typical amount of calories, or even the normal basal calories for their height, age, weight, and activity level. Instead, they cut their calories significantly, which puts their bodies into semi-starvation. Their bodies are now fighting to use whatever calories are available for survival. These kinds of studies don’t provide a meaningful comparison of diets under normal metabolic conditions. Studies that do not force calories to be restricted usually show a significant advantage of very low carb diets over their converse.
Another problem with diet comparison studies has to do with controlling variables that may affect the outcome. If a low fat diet demands that food intake be cut significantly, that also implies carbohydrates will be cut, too. From the article Calories, fat or carbohydrates? Why diets work (when they do):
"Virtually any diet that significantly restricts the number of calories consumed, even a diet that is described as low-fat (because the subjects are instructed to reduce the proportion of fat calories they consume), will cut the total amount of carbohydrate calories consumed as well. This is just simple arithmetic. If we cut all the calories we consume by half, for instance, then we’re cutting the carbohydrates by half, too. And because these typically constitute the largest proportion of calories in our diet to begin with, these will see the greatest absolute reduction. If we preferentially try to cut fat calories, we’ll find it exceedingly difficult to cut more than 400 or 500 calories a day by reducing fat — depending on how much fat we were eating to begin with — and so we’ll have to eat fewer carbohydrates as well."
"Put simply, low-fat diets that also cut significant calories will cut carbohydrates significantly as well, and often by more than they cut fat." - Gary Taubes
And what about the quality of carbohydrates on a so called low fat diet? Sugar, white flour, and other refined carbohydrates are typically replaced with whole grains and fiber. The fact that these kinds of diets, when adhered to strictly, can often produce results shouldn’t be surprising. However, it also shouldn’t be surprising when diets that cut carbohydrates even more result in a larger weight loss.
How fast do you lose weight on a low carb diet?
From the book, “The New Atkins for a New You”:
"Most people lose pounds quickly and steadily in the first few weeks of Atkins-in fact, some people lose up to 15 pounds in the first two weeks on the program. But numerous factors influence your individual weight loss pattern. If you just have a few pounds to lose, they may be more resistant to your efforts. Men tend to lose more quickly than women do. Younger people typically have an advantage over the middle-aged or older. Hormonal changes, such as menopause, can definitely slow your metabolism and make it more difficult to banish pounds. Some people naturally have a slower metabolism. Certain prescription drugs can also interfere with weight loss. Your spouse or friend may well lose at a different rate than you do. Just remember that getting slim isn’t a contest. Rather it’s a process of discovering how your own body works." - Dr. Eric C. Westman, Dr. Stephen D. Phinney, Dr. Jeff S. Volek
Is a low carb diet “natural” for people or is it just a “fad diet?"
Carbohydrate restriction is the most “natural” way of eating for human beings. It’s not just for weight loss. For 2.5 million years, humans have been eating pretty much the same kind of variety of foods like meat, fish, roots, leafy vegetables, and some low-sugar fruits. From an evolutionary standpoint, this kind of diet should be optimal since it’s what we’ve evolved to thrive on. This led many to the establishment of the “paleo diet.”
The paleo diet is perfectly safe and effective, not only for losing weight, but as a “normal” diet. (We’ve only been farming for the last 12,000 years of human existence, so grains have been a relatively new addition to the human diet. Vegetable oils have only been around for about 100 years.) Paleo dieters have always been skeptical of any kind of newer foodstuffs since they may have unintended consequences. Their concerns range from scientifically accurate (trans-fats are bad, naturally occurring fats are good, white flour is bad, etc.) to being a bit on the paranoid side (no dairy products, fluoride is bad, artificial sweeteners are bad, etc.)
My opinion is that the paleo diet is a beginning, not an end. It’s okay to be skeptical of new kinds of food, but rejection of those new foods should be based on science, not blind acceptance of a dogma. (That’s how we got stuck with the lipid hypothesis.) I drink diet soda and cook with sucralose because they’ve been shown to be safe. I’ll buy organic food because it may taste better, but not because it’s safer (it’s not) or healthier. An example of the paleo diet and its rationale can be found in detail from the Weston A. Price Foundation.
The take away from this is that the paleo, or “natural” human diet was essentially low carb. Anyone who tells you humans are “designed” to be vegetarians is very misinformed or has an agenda.
From the article, Good Calories, Bad Calories: What Really Makes Us Fat? by Gary Taubes:
“Although nutritionists don’t like to talk about this in an era that considers fruits and vegetables to be the sine qua non of a healthful diet, animal products happen to contain all the amino acids, minerals and vitamins essential for health, with the only point of controversy being vitamin C. And the evidence suggests that the vitamin C content of meat products is more than sufficient for health, so long as the diet is indeed carbohydrate-restricted, absent the refined and easily digestible carbohydrates and sugars that would raise blood sugar and insulin levels and so increase our need to obtain vitamin C from the diet.”
What about foods high in fat and cholesterol? Are they safe?
There are three kinds of dietary fat: saturated, monounsaturated, and polyunsaturated. The fat in foods usually contain a combination of all three. This may come as a surprise to some people who assume foods only have one type of fat. For example, olive oil is universally accepted as healthy because it has been identified as a source of monounsaturated fat. However, 14% of olive oil is saturated fat and 8% polyunsaturated fat. Lard, which people assume is a wholly saturated fat, contains just 40% saturated fat; in fact 45% of lard is monounsaturated fat, and 15% polyunsaturated fat!
The advice trumpeted by many health organizations is to minimize saturated fat and increase monounsaturated fat. Let me get this out of the way...
SATURATED FAT IS SAFE!
Evidence:
- “A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD.”
- Saturated Fat Is Not Associated With CVD, Evidence of Publication Bias
- The Dirty Little Secret of the Diet-Heart Hypothesis
I know. This is counter to what you’ve been told, but it’s true. I’ll try to explain in as little words as possible...
Your total cholesterol, as shown on a standard cholesterol test, can be broken down into categories: Low-Density Lipoprotein, or LDL, is known as “bad” cholesterol. High-Density Lipoprotein, or HDL, is known as “good” cholesterol. (These characterizations of LDL and HDL are gross oversimplifications and will be addressed in the next paragraph.) Lastly, there are Triglycerides. Some cholesterol tests provide a report of Very Low-Density Lipoprotein, or VLDL. This value is calculated using the formula: triglycerides/5. High levels of LDLs and triglycerides and low levels of HDLs in the bloodstream have been linked to increased risk of heart disease and stroke. The traditional rule of thumb is the higher your HDL and the lower your LDL and triglycerides, the better your cholesterol. However, LDLs can be further subdivided by size: large, buoyant LDL (pattern A) and small, dense LDL (pattern B or sdLDL). Relatively recent research has shown that a high level of oxidized LDL is a much better predictor for atherosclerosis than LDLs alone. It is the small, dense LDL particles that are prone to oxidation; therefore, it is those we want to minimize. Studies in the past have shown saturated fat increases total LDL and low fat diets can lower total LDLs.* However, we have now discovered that saturated fats also decrease sdLDL while high carb diets do the reverse! (A standard cholesterol test will not give you an accurate profile of your LDL particles. However, there are a few labs that are now offering this service if you know to ask. The most common one is called a Vertical Auto Profile or VAP test.)
*High fat diets raise HDLs and lower triglycerides. High carbohydrate diets can have the opposite effect.
The classification of HDLs, LDLs, and VLDLs as cholesterol is a misnomer. They are proteins that transport cholesterol and are not cholesterol themselves. VLDLs are made in the liver and used to transport fat and cholesterol from the liver to other cells around the body. As VLDLs lose fat they shrink, and transform into LDLs.
From an interview with one of the world’s leading experts on cholesterol particles, Ron Krauss:
We’ve talked about the LDL. The precursors are VLDL, very low density lipoproteins that contain predominantly triglyceride, which is another fat that’s used for energy and storage. As that triglyceride is broken down in the blood, the triglycerides is used by tissues to store fat, that’s one reason we get fat because the triglyceride moves into the fat tissue, or it can be burned in the muscle and that’s how we get energy when we exercise as we should. As the triglycerides are removed, the particles shrink. LDL comes from VLDL, and depending on the metabolic conditions, and the type of VLDL that are in the blood, you can either get the larger or the smaller. All of us have varying amounts of the large and small. It’s not as if we have just one or the other. It’s the proportions of these particles that can differ.
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Our own data have fairly clearly shown with moderate elevations, say 150, if you have the larger particles you have very low risk of heart disease, and if you have predominantly smaller particles, the risk goes up significantly.
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The traffic in the system is guided by proteins and that ultimately comes from DNA. So the genetics work largely through proteins. In the case of LDL, there are some interesting variations in the protein that we think are quite relevant to what happens to the particle. In the case of LDL, the major protein is ApoB. That is a very large protein that has many components within it that assume different configurations depending on whether the particle is larger or smaller. It actually starts in the VLDL. So the ApoB single protein on the The VLDL has to hold together a very large particle and stay on the particle as it gets smaller and smaller. So it changes its configuration in ways that are very distinct. Once you get to the very smallest particle–That ApoB is squeezed into a little ball, so its ability to be recognized by receptors gets impaired. So what happens is that the smaller LDL have reduced receptor uptake, and that’s something that’s very relevant to the pathology of small LDL. And it has to do with the changes in protein.
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That’s why they wind up in the arteries. The other thing is that these particles tend to stay the bloodstream longer.
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What happens is the particles that have reduced receptor uptake, the ones that we’re talking about that are more damaging to the arteries don’t get taken up by the liver as rapidly as we’d like them to, so they circulate in the body a longer time, they can get modified, they can get oxidized and they get more toxic to the artery. So to the extent these don’t get removed by them, these particles are a little bit like the Flying Dutchman. in the opera that has no place to land. Circulating and circulating. And more and more damaging to the arteries.
HDLs transport fat and cholesterol back to the liver in order to be recycled. More HDLs in your bloodstream means lower risk for heart disease. In fact, the (inverse) correlation between HDLs and disease is much better than the one for LDLs.
HDL is a marvelous and very ancient biological phenomenon for detoxifying tissues. It has many functions that appear to be important for health beyond scooping up cholesterol. Some components of HDL can fight infection. There have been studies of its role in reducing the risk of parasitic infections of some kinds. HDL is one of the more complex systems in the blood, even though it’s a small little guy circulating around and it looks fairly simple, it turns out there’s many components of HDL geared in to be flexible in protecting the body from bad things in the tissues.
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Macrophages are an interesting cell. These are the garbage collectors in the tissues. If we didn’t have them, we’d be subject to many serious infections. But the fact that we have them puts us at risk for, when they get overly stimulated, and pick up too much cholesterol, and in particular when they pick up oxidized cholesterols, these macrophages can be very bad things because they fill up with so much cholesterol and if they end up in the artery then they actually initiate the formation of plaques which can enlarge and lead to ruptures and heart attacks.
There is nothing inherently bad with LDLs. They are required for your body to function. The LDLs become a problem when they are small since they are prone to get stuck in the arterial walls, oxidize, cause inflammation, and lead to plaque. Therefore, the primary goal is not to minimize LDLs; it is to minimize small, dense LDLs.
...the individuals who have a predominance of the smaller LDL particles, either due to genetics or diet or obesity, the so-called pattern B profile, we now know that those LDL are coming through a very specific pathway. It’s not just a matter of breaking down larger LDL into smaller LDL. It’s a completely different pathway from which those particles originate. And that pathway is influenced by things like carbohydrates, diabetes, metabolic syndrome and obesity. All of which turn on a very specific pathway which is different from the pathway for making the larger particle LDL. So the metabolism is actually fairly complex.
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The fact is that if you’re insulin resistant, you have an increased production of lipoproteins, and the VLDL that come out of the liver tend to have more triglycerides on them. Those are the ones that tend to form the smaller LDLs.
This video contains a more detailed explanation: Exposing the Cholesterol Myth
...what represents too much triglycerides in the bloodstream? There are several observations to help us make this determination:...
- When fasting triglycerides are 133 mg/dl or greater, 80% of people will show show at least some degree of small LDL particles.
- When fasting triglycerides are 60 mg/dl or less, most (though not all, since genetic factors enter into the picture) people will show little to no small LDL particles.
- When fasting triglycerides are 200 mg/dl or greater, small LDL particles will dominate and large LDL particles will be in the minority or be gone entirely.
- When triglycerides are 88 mg/dl or greater after eating, then risk for heart attack is doubled. Non-fasting triglycerides in the 400+ mg/dl range are associated with 17-fold greater risk for heart attack.
Curiously, while fat intake (i.e., triglyceride intake) plays a role in determining postprandial triglyceride blood levels, it’s carbohydrate intake that plays a much larger role.
This brings us to our second dietary revelation:
DIETARY CHOLESTEROL IS HEALTHY!
Your body needs cholesterol to survive. Cholesterol is needed for many bodily functions and serves to insulate nerve fibers, maintain cell walls and produce vitamin D, various hormones and digestive juices. The “high” amounts of cholesterol in foods like eggs that people eat is nothing compared with the 1,000 milligrams their livers produce naturally. Humans have a negative feedback mechanism that regulates cholesterol levels. Herbivores don’t. So it’s no wonder that studies involving rats and rabbits show a positive correlation of dietary cholesterol and atherosclerosis, but human studies don’t.
From Cholesterol and Beyond: The Research on Diet and Coronary Heart Disease by A. Stewart Truswell:
Dietschy and Wilson [207] explained why animals have different responses to cholesterol feeding. In all species on very low cholesterol intake (e.g., human vegans) the body’s cholesterol comes from endogenous synthesis. In rabbits fed cholesterol (not part of their normal diet) more cholesterol is absorbed than is normally synthesised and excretion as bile acids cannot increase. In humans, cholesterol absorption is limited; the amount absorbed can be compensated by inhibited synthesis alone, so the body’s cholesterol pool is only slightly enlarged. In dogs and rats, inhibited synthesis and increased bile acid formation compensate for a large increase of cholesterol absorption: there is only a modest expansion of the body’s cholesterol pool.
207. Dietschy John M. & Wilson Jean D. (1970) “Regulation of cholesterol metabolism,” (third of three parts). N Engl J Med, 282: 1241–1249.
Dietary cholesterol can have a relatively small influence on serum cholesterol levels, but it depends on many factors. Dietary cholesterol has a greater effect on serum cholesterol if it is added to a low cholesterol diet. The effect of dietary cholesterol also depends on a person’s genetics. People with the 4/4 genotype of apolipoprotein E will have a higher rise of serum total cholesterol than those with other genotypes. However, this is not something to worry about.
From section 13.7 of “Regulation of cholesterol metabolism:”
It was fairly clear, from the time of Keys’ square root equation that adding larger amounts of dietary cholesterol have proportionally smaller effects on serum cholesterol. Hopkins [215] confirmed this in mathematical analyses of published data from studies with controlled diets supplied by a metabolic kitchen (Fig. 13.1).
His new finding was that cholesterol has a greater effect on serum cholesterol if it is added to a low cholesterol diet; at moderate (basal) cholesterol intake serum cholesterol changes little. Reading from his graph, 500 mg added dietary cholesterol would increase serum cholesterol by 0.60 mmol/l (20 mg/100 ml) if baseline cholesterol intake was zero; the corresponding increase would only be 0.08 mmol/l (3 mg/100 ml) when baseline was 500 mg cholesterol per day.
In the last meta-analysis of the century, Howell et al. [216] collected 9 different published prediction equations for serum cholesterol responses to changes in cholesterol intake. The most recent predictions for 100 mg/day increase in dietary cholesterol had come down from about +0.1 mmol/l (+4 mg/100 ml) to about +0.06 mmol (+2 mg/100 ml).
There has been no clear epidemiological evidence that addition of one egg to the daily diet increases the risk of CHD [217].
215. Hopkins PN (1992) Effects of dietary cholesterol on serum cholesterol: a meta-analysis and review. Am J Clin Nutr, 55: 1060–1070.
216. Howell WH, McNamara DJ, Tosca MA, Smith BT & Gaines JA (1997) Plasma lipid and lipoprotein responses to dietary fat and cholesterol a meta-analysis. Am J Clin Nutr, 65: 1747–1754.
217. Hu FB, Stampfer MJ Rimm JE, et al. (1999) A prospective study of egg consumption and risk of cardiovascular disease in men and women. JAMA, 281: 1387–1394.
To put this data in practical terms:
Decreasing cholesterol consumption from 400 mg a day, the average American intake in the 1990s, to the 300 mg a day recommended by the National Cholesterol Education Program would be expected to reduce cholesterol levels by 1 to 2 mg/dl, or a decrease of perhaps 1%. - Gary Taubes
If you want to improve your serum cholesterol profile, fats (aside from trans-fat) provide a net benefit. Carbohydrates, on the other hand, can be detrimental.
Carbohydrate is much more of a factor than many people realize. People think that blood cholesterol comes from dietary cholesterol. That’s definitely not true. Dietary cholesterol coming in eggs and shellfish has modest effects on cholesterol. It’s much more effected by the type of fat and carbohydrate. The fat that causes LDL to go up is saturated fat. Animal fat. We’ve shown that it tends to affect the larger LDL, interestingly. What we tend to think of as bad fat primarily affects the less bad form of LDL, whereas carbohydrates, in a somewhat counterintuitive way, it’s starches and sugars that raise the bad form of LDL. [...] If the body gets more starch, it will use it to stimulate the storage of more fat. - Ron Krauss
More details and links to studies can be found here.
Why were fats and cholesterol so vilified for so many years?
Here’s another two excerpts from the documentary “Fat Head” by Tom Naughton that provide a visual explanation:
If you want more information, read Gary Taubes’ book, “Good Calories, Bad Calories.” Taubes provides a detailed history of the anti-fat movement in chapter 3 of his book. Dr. Mike Eades has a great article on the infamous Time magazine article on cholesterol from 1984.
Basically, any fat that occurs in nature without processing is good to consume. If it needs to be made in a factory, like corn oil, then it’s probably bad. (Canola oil is an exception.) Any fat or oil that starts with “partially hydrogenated” is a trans-fat and should be avoided. Fats that are largely saturated (e.g., coconut oil) and largely monounsaturated (e.g., olive oil, canola oil, high-oleic safflower oil, etc.), are good. Fats from animal products are, of course, good for you.
Essential fatty acids, or EFAs, are fatty acids that must be obtained from the diet for good health. The body cannot produce these fats on its own. There are two families of EFAs: omega-3 and omega-6. These two compete with each other to get into cell membranes. Ideally, you should have a 1:1 ratio of omega-3 to omega-6 polyunsaturated fat in your diet. However, this may be very difficult to achieve. A 1:2 or 1:3 ratio is a more realistic goal. Fish oil supplements are recommended since there’s evidence that omega-3 fats burn off faster than others.
From Gary Taubes' book:
“Consider a porterhouse steak with a quarter-inch layer of fat. After broiling, this steak will reduce to almost equal parts fat and protein. Fifty-one percent of the fat is monounsaturated, of which 90 percent is oleic acid. [That’s the same kind of fat that’s in olive oil –Sizzlechest] Saturated fat constitutes 45 percent of the total fat, but a third of that is stearic acid, which will increase HDL cholesterol while having no effect on LDL. (Stearic acid is metabolized in the body to oleic acid, according to Grundy’s research.) The remaining 4 percent of fat is polyunsaturated, which lowers LDL cholesterol but has no meaningful effect on HDL. In sum, perhaps as much as 70 percent of the fat content of a porterhouse steak will improve the relative levels of LDL and HDL cholesterol, compared with what they would be if carbohydrates such as bread, potatoes, or pasta were consumed. The remaining 30 percent will raise LDL cholesterol, but will also raise HDL cholesterol and will have an insignificant effect, if any, on the ratio of total cholesterol to HDL. All of this suggests that eating a porterhouse steak in lieu of bread or potatoes would actually reduce heart-disease risk, although virtually no nutritional authority will say so publicly. The same is true for lard and bacon.”
BTW, I’ve seen people cite studies claiming saturated fats lead to insulin resistance. This so-called evidence is highly dubious.
Are low carb diets difficult to follow?
Any diet is a challenge. In fact, most people who go on diets will fail. Here’s the good news, low carb diets can be relatively easy to follow. High fat diets satiate you better than high carbohydrate diets. Generally, low carb diets aren’t calorie restricted. Eat until your full; just don’t go over you carb allotment.
You can eat tasty and fatty foods like steak, eggs, nuts, heavy cream, etc. You are also allowed natural and artificial sweeteners that don’t raise your blood sugar, like sucralose, aspartame, stevia, etc. so no need to deny your sweet tooth. Yes, pasta, bread, potatoes, and other starchy foods are out, but there are clever substitutes out there if you look. I’ll be providing more tips for substituting high carb foodstuffs later on in the recipes section.
How do low carb diets compare to other kinds of diets?
Here’s a video from Dr. Chris Gardner, a director of Nutrition Studies and an associate professor of medicine at Stanford. This self described vegetarian nutritionist compared four different diet plans from high carb/low fat to low carb/high fat: Ornish, LEARN, Zone, and Atkins. You may be surprised what he found.
The Battle of the Diets: Is Anyone Winning (At Losing?)
I recommend watching the entire video, but I’ll give you the scoop: low carb diets were the best at losing weight, keeping the weight off, were the easiest to follow (least hardest would probably be more accurate), and was the only one that yielded an improvement in blood lipids. (Sadly, Dr. Gardener was surprised at the outcome.)
Here’s an interview with Dr. Mike and Mary Eades about diets and hunger: Diets and Hunger
Aside from watching what I eat, what else should I do?
The number one tip for anyone starting any kind of diet: LEARN TO COOK!
Frozen dinners, prepackaged food, and most fast-food stuff suck. You need to make you own meals whenever possible. A lot of recipes can be adapted to become low carb versions with a little ingenuity. Check out the recipes section for some common substitutions and recipe ideas.
What’s the deal with caffeine?
Atkins used to claim caffeine messes with blood sugar. The “The New Atkins for a New You” book has reversed this position:
The bulk of your daily fluids should come from water, clear broth, and herb teas. Drinking coffee and other caffeinated beverages increases urine output, but research indicates that it doesn’t contribute to creating water or electrolyte imbalances.[1] Caffeine also gently assists the body in burning fat.[2] - Dr. Eric C. Westman, Dr. Stephen D. Phinney, Dr. Jeff S. Volek
1. Lawrence E. Armstrong, Douglas J. Casa, Carl M. Maresh, Matthew S. Ganio, “Caffeine, Fluid-Electrolyte Balance, Temperature Regulation, and Exercise-Heat Tolerance,” Exerc Sport Sci Rev. 2007;35(3):135-140.
2. D. Costill, G. Dalsky, W. Fink, “Effects of caffeine ingestion on metabolism and exercise performance.,” Med Sci Sports Exer 10:155-158, 1978.
In fact, if you combine caffeine with ephedrine, you can lose even more weight. The S.P.E.E.D. book describes how to do it. You can also find further information by researching the "ECA stack" (ephedrine-caffeine-aspirin), a common take on this method (but out of the scope of this wiki)
Can I have alcoholic beverages?
Here’s what Atkins said in his “Dr. Atkins’ New Diet Revolution (3rd Ed.)” book:
“The body burns alcohol for fuel when alcohol is available. So when it is burning alcohol, your body will not burn fat. This does not stop weight loss; it simply postpones it. Since alcohol does not get stored as glycogen, you immediately get back into lipolysis after the alcohol is used up. But keep in mind that alcohol consumption may increase yeast-related symptoms in some people and interfere with weight loss. If it does not slow your weight loss, and occasional glass of wine is acceptable once you are out of Induction so long as you count the carbohydrates in your daily tally.” “If you have added alcohol to your regimen and suddenly stop losing weight, discontinue your alcohol intake.”
What is Ketosis?
The following has been lifted directly from About.com:
“...Ketosis merely means that our bodies are using fat for energy. Ketones (also called ketone bodies) are molecules generated during fat metabolism, whether from the fat in the guacamole you just ate or fat you were carrying around your middle. When our bodies are breaking down fat for energy, most of it gets converted more or less directly to ATP. (Remember high school biology? This is the ‘energy molecule.’) But ketones are also produced as part of the process.
When people eat less carbohydrate, their bodies turn to fat for energy, so it makes sense that more ketones are generated. Some of those ketones (acetoacetate and ß-hydroxybutyrate) are used for energy; the heart muscle and kidneys, for example, prefer ketones to glucose. Most cells, including the brain cells, are able to use ketones for at least part of their energy. But there is one type of ketone molecule, called acetone, that cannot be used and is excreted as waste, mostly in the urine and breath (sometimes causing a distinct breath odor).
If enough acetone is in our urine, it can be detected using a dipstick commonly called by the brand name Ketostix (though there are other brands, as well). Even though everyone is generating ketones continuously, this detection in the urine is what is commonly called ‘ketosis.’”
I strongly recommend reading Dr. Mike Eades excellent post about “Metabolism and Ketosis” for more information.
Also, A Guide to Ketosis contains lots of information for bodybuilding.
What is the Glycemic Index?
The Glycemic Index is a measure of the effects of carbohydrates on blood sugar levels. This index measures how much your blood glucose increases in the two or three hours after eating certain foods. The scale is based on an ingestion of a fixed portion of carbohydrate (usually 50g) and is calibrated on an index value of 100 for pure glucose. A low GI food will release glucose more slowly and steadily. A high GI food causes a more rapid rise in blood glucose levels.
Another term you may have heard is Glycemic Load. This is a ranking system for carbohydrate content in food portions based on their Glycemic Index and the portion size. The usefulness of Glycemic Load is based on the idea that a high Glycemic Index food consumed in small quantities would give the same effect as larger quantities of a low Glycemic Index food on blood sugar. For example, the carbohydrate in watermelon has a high GI, but there isn’t a lot of it; so, watermelon’s Glycemic Load is relatively low.
The next logical step was to examine the effects foods had on insulin. The Insulin Index is a measure used to quantify the typical insulin response to various foods. The index is similar to the Glycemic Index and Glycemic Load, but rather than relying on blood glucose levels, the Insulin Index is based upon blood insulin levels. What is interesting is that high-protein foods, like meats, elicit insulin responses that were disproportionately higher than their glycemic responses. (I’ll explain this effect in great detail shortly.)
I find the Glycemic Index and Glycemic Load are useful for determining foods that should have a relatively low impact on blood sugar. But be careful. The GI/GL values should be used only as a rule of thumb. Different people will have different reactions to the foods in the index, especially people who are already insulin resistant. The type of food, its ripeness, processing, the length of storage, cooking methods, and its variety can have a significant effect on the GI/GL. The GI/GL of foods is determined under experimental conditions after an overnight fast, and might not apply to foods consumed later during the day because glycemic response is strongly influenced by the composition of the previous meal, particularly when meals are consumed within an interval of few hours.
The Insulin Index values are much less reliable indicators. The Insulin Index is affected by all the problems associated with the Glycemic Index and Glycemic Load. On top of that, it implies the insulin response of protein-rich foods impact weight loss in the same way as carbohydrates. They do NOT. The missing piece of the puzzle is glucagon.
From the excellent description of Insulin and Glucagon:
Consumption of carbohydrates triggers release of insulin from beta cells. Alpha cells become inhibited and cease to secrete glucagon. Taken together, these actions produce a rapid return to fasting blood sugar levels and storage of glucose as glycogen or lipid.
A protein-rich meal leads to release of both insulin and glucagon. The latter stimulates gluconeogenesis and release of the newly formed glucose from the liver to the blood stream. The very moderate rise in insulin associated with the protein meal stimulates uptake of the sugar formed in the liver by muscle and fat tissue. - Robert S. Horn
Therefore, indexing the levels of insulin without taking into account the other hormonal effects of the foods’ digestion paints a too simplistic and misleading view. Glucagon mitigates the effects of insulin. Tracking the insulin response without taking into account glucagon renders the index useless, IMHO.
Perhaps the biggest reason I don’t take much stock in any of these indexes is that they do not take into account fructose. Fructose, by all accounts, is much more damaging than glucose to your metabolism. There has even been some research that showed fructose is the main cause of insulin resistance.
The closest thing I’ve found to a “fructose index” is this site: Foods highest in Fructose
An excellent example is blueberries. They have a GI and GL of 40 and 6, respectively. Those numbers are considered low. However, blueberries are one of the fruits highest in fructose. Strawberries fall into the same category.
Is fructose really toxic?
Some of you may have seen or heard about the lecture called “Sugar: The Bitter Truth,” by Dr. Robert Lustig where he claims sugar is a “toxin.” I would suggest you watch the hour and a half long video yourself and read Gary Taubes’ article on the subject, but I’ll try to summarize it.
The metabolism of fructose is different than other sugars. It can be quite harmful even in relatively small amounts because of the way it’s processed. Unlike glucose, only the liver can metabolize fructose. Fruit contains lots of fiber, which slows the digestion of fructose. Therefore, the effects of fructose are mitigated (but not entirely eliminated) by the fiber. This is why Lustig says the sugar in fruit juice, even ones not sweetened by H.F.C.S., is still bad for you. It’s not a matter of excess calories. It’s the specific effects on the body that makes fructose undesirable.
Sometimes I feel run down on a low carb diet. Why?
Some people who dive into a low carb lifestyle report a sense of sluggishness and general inability to mentally focus when they start. People who exercise complain of a drop in performance in their workouts. This can happen, but don’t worry; it’s a normal and temporary part of your body’s transition to a low carb ketogenic lifestyle.
There is ample evidence that switching to a ketogenic diet will cause an initial reduction in physical stamina. Fortunately, this is relatively short lived as long as you do not break from the low carb regimen. From the paper, Ketogenic diets and physical performance:
There are to date no studies that carefully examine the optimum length of this keto-adapataion period, but it is clearly longer than one week and likely well advanced within 3–4 weeks. The process does not appear to happen any faster in highly trained athletes than in overweight or untrained individuals. This adaptation process also appears to require consistent adherence to carbohydrate restriction, as people who intermittently consume carbohydrates while attempting a ketogenic diet report subjectively reduced exercise tolerance. - Stephen D. Phinney
Another cause of fatigue is a lack of sodium and/or potassium in the diet. When you were eating lots of carbs, your kidneys were retaining fluid. Restoring your insulin to normal levels causes rapid release of fluid taking sodium and potassium along with it. The good news is that there’s a very simple solution: eat something salty. Your goal is to ingest approximately 2 cups of broth, 1/2 teaspoon of salt, or 2 tablespoons of regular soy sauce daily assuming your net carb intake is less than 50 grams. Dill pickles are also ideal, but make sure you read the ingredients. Some brands, like Mt. Olive, inexplicably add fructose. I also discovered, thanks to the regulars in this thread, that almonds are high in potassium and VERY low in net carbs. Uziel recommends Morton Lite Salt, which contains potassium/magnesium/sodium.
From the paper mentioned above:
With these supplements maintaining daily intakes for sodium at 3–5 g/d and total potassium at 2–3 g/d, our adult subjects were able to effectively maintain their circulatory reserve (ie, allowing vasodilatation during submaximal exercise) and effective nitrogen balance with functional tissue preservation. - Stephen D. Phinney
Dr. Mike Eades provides some tips for starting (or restarting) low carb: Tips & tricks for starting (or restarting) low-carb
Isn’t salt dangerous?
The best evidence to date shows that, for most people, salt reduction offers only a modest health benefit, if any. Reducing salt from 8 grams to 4 grams a day made little difference in blood pressure: 1.7/1.1 mmHg in normotensives (those with normal blood pressure). Hypertensives (those with high blood pressure) made more significant losses: 8.3/4.4 mmHg.
However, salt is not the major driver of blood pressure and there’s no compelling evidence that hypertension is caused by it. Maybe that’s why the Kuna Indians don’t get hypertension when they live a non-industrial, grain-free lifestyle despite eating more salt than the average American?
Blood pressure is also affected by water retention. Low carb diets deplete glycogen stores, which release water out of the body, thus lowering blood pressure. (FYI, each molecule of glycogen is bound to four molecules of water. This is why low carb dieters lose so much water weight in the beginning.)
Medical science hasn’t conclusively determined what causes hypertension, but the number one suspect seems to be uric acid. If you’re interested in learning more, this presentation explains it in great detail: Uric Acid, Fructose and Hypertension. Fructose consumption leads to uric acid, which leads to high blood pressure and a fatty liver.
In fact, fructose can be linked to a whole array of disorders. Watch this presentation by Dr. Richard Johnson where he explains (in exquisite detail) how fructose leads to high blood pressure, hypertension, fatty liver, vascular damage, insulin resistance, diabetes, and more:
How much protein should I consume and is too much dangerous?
From the paper, “Ketogenic diets and physical performance,” the amount of protein the research suggests is optimal is described:
The third dietary factor potentially affecting physical performance is adjusting protein intake to bring it within the optimum therapeutic window for human metabolism. The studies noted herein [13-15,20] demonstrate effective preservation of lean body mass and physical performance when protein is in the range of 1.2 – 1.7 g/kg reference body weight daily, provided in the context of adequate minerals. Picking the mid-range value of 1.5 g/kg-d, for adults with reference weights ranging from 60–80 kg, this translates into total daily protein intakes 90 to 120 g/d. This number is also consistent with the protein intake reported in the Bellevue study [9]. When expressed in the context of total daily energy expenditures of 2000–3000 kcal/d, about 15% of ones daily energy expenditure (or intake if the diet is eucaloric [a eucaloric diet is one where the calories are adjusted to maintain the current weight of the subject –Sizzlechest]) needs to be provided as protein. - Stephen D. Phinney
The importance of protein is explained in the book, “The New Atkins for a New You”:
A number of studies have shown that consuming protein is more satiating than consuming either carbohydrate or fat.[1] ... When you replace some carbohydrate with protein in your diet, you experience fewer fluctuations in blood sugar. Digesting and metabolizing protein consumes more than twice the energy (about 25%) as processing either carbohydrate or fat.[2] This means you will burn more calories when digesting protein then when digesting the two other macronutrients. Higher-protein diets have been linked to prevention of obesity and muscle loss, as well as reduced risk of developing metabolic syndrome, type 2 diabetes, and heart disease.[3] ... Research shows that higher-protein diets are associated with greater retention of lean body mass during weight loss -- independent of calorie intake -- providing strong evidence that diets lower in carbs and higher in protein have beneficial effects on body composition.[4]
1. G. H. Anderson, S. E. Moore, “Dietary proteins in the regulation of food intake and body weight in humans,” J Nutr. 2004 Apr;134(4):974S-9S.
2. E. Jéquier, “Pathways to obesity,” Int J Obes Relat Metab Disord. 2002 Sep;26 Suppl 2:S12-7.
3. Frank Q. Nuttall, Kelly Schweim, Heidi Hoover, Mary C. Gannon, “Metabolic effect of a LoBAG30 diet in men with type 2 diabetes ,” Am J Physiol Endocrinol Metab 291: E786-E791, 2006. First published May 23, 2006; doi:10.1152/ajpendo.00011.2006.
4. James W. Krieger, Harry S. Sitren, Michael J. Daniels, and Bobbi Langkamp-Henken, “Effects of variation in protein and carbohydrate intake on body mass and composition during energy restriction: a meta-regression,” American Journal of Clinical Nutrition, Vol. 83, No. 2, 260-274, February 2006.
The following table was provided in the book, “The New Atkins for a New You”:
While low carb diets do benefit from higher protein intake, they are not considered high-protein diets. Nevertheless, many people are still concerned. The book, “The New Atkins for a New You” addresses this issue:
...most of the concerns about eating too much protein are unfounded, in that they’re based on limited or flawed research. For example, the misconception that a high protein intake can damage kidneys probably arose from the fact that individuals who already have advanced kidney disease cannot clear away the waste from even a moderate protein intake. There’s absolutely no evidence that any healthy person has experienced kidney damage from eating the amount of protein consumed on Atkins. ... A high-protein diet has been shown to increase calcium excretion in the urine, prompting concern about a negative effect on bone health. However, recent research indicates that the loss of calcium is offset by increased absorption of calcium and the net effect is increased bone mass[6] Concerns about and increased risk of developing osteoporosis in healthy individuals are likewise unfounded.[7] - Dr. Eric C. Westman, Dr. Stephen D. Phinney, Dr. Jeff S. Volek
6. Robert P. Heaney and Donald K. Layman, “Amount and type of protein influences bone health,” American Journal of Clinical Nutrition, Vol. 87, No. 5, 1567S-1570S, May 2008.
7. Ibid.
How come Asians aren’t fat with all the rice they eat?
From TheCosmicMuffet:
Some of them are. Many of them are starving, and food shortages are a common thread in Chinese history, particularly. The rice was brown until recently. They didn’t have refined sugar in the diet until recently. They invented meth and it gets a lot of use. Fish in the diet.
Also the term ‘Asian’ is ludicrously broad. Vegetarian Hindus, for example, are traditionally fatter than non vegetarians, from the anecdotes I’ve heard, but it got much worse when sugar was introduced. Rice wasn’t a historical Indian staple--the historical vegetarian model in India was dairy based. Indonesian peninsula peoples had a tropical diet that was similar to Kitavans, only with more land animals and other fruit involved. Himalayans and Mongolians are all heavily herders and hunters. Inland China has rice, like you say, but had traditional integrated farming with animals and a variety of vegetables. The Japanese had fish as their dietary staple for the most part, since there’s no place anybody lived that wasn’t in range of fresh fish. They had virtually no dairy and a reasonable supply of pork.
What is certain is that people who get high sugar high carb diets have higher obesity rates. What is vague is why so many people can tolerate a moderate-to-high carb diet even when the diet is apparently low fat. Inflammatory response seems important, and fish, coconut milk, cocoa, mint, and some other spices seem to modulate that to a great extent. Also, if someone is short on food, then they go hungry, and the body just makes do. Only the most extremely unhealthy high carb diet actually can overcome starvation--for instance wheat to starving people in Somalia, or sugar cane for slaves in the Caribbean.
Also gluten is an antagonist which rice (and tubers) don’t have.
Do I have to worry about nitrates in processed meats and bacon?
From the article Nitrate: a Protective Factor in Leafy Greens:
Nitrate (NO3) is a molecule that has received a lot of bad press over the years. It was initially thought to promote digestive cancers, in part due to its ability to form carcinogens in the digestive tract. As it’s used as a preservative in processed meats, and there is a link between processed meats and gastric cancer[1], nitrate was viewed with suspicion and a number of countries imposed strict limits on its use as a food additive.
But what if I told you that by far the greatest source of nitrate in the modern diet isn’t processed meat-- but vegetables, particularly leafy greens[2]? And that the evidence specifically linking nitrate consumption to gastric cancer has largely failed to materialize? For example, one study found no difference in the incidence of gastric cancer between nitrate fertilizer plant workers and the general population[3]. Most other studies in animals and humans have not supported the hypothesis that nitrate itself is carcinogenic[4,5,6]. This, combined with recent findings on nitrate biology, has the experts singing a different tune in the last few years.
1. Santarelli RL, Pierre F, Corpet DE, “Processed meat and colorectal cancer: a review of epidemiologic and experimental evidence,” Nutr Cancer, 2008;60(2):131-44.
2. Hord NG, Tang Y, Bryan NS, “Food sources of nitrates and nitrites: the physiologic context for potential health benefits,” American Journal of Clinical Nutrition, 2009 Jul;90(1):1-10, Epub 2009 May 13.
3. Al-Dabbagh S, Forman D, Bryson D, Stratton I, Doll R, “Mortality of nitrate fertiliser workers,” British Journal of Industrial Medicine, 1986 Aug;43(8):507-15.
4. Maekawa A, Ogiu T, Onodera H, Furuta K, Matsuoka C, Ohno Y, Odashima S, “Carcinogenicity studies of sodium nitrite and sodium nitrate in F-344 rats,” Food Chem Toxicol., 1982 Feb;20(1):25-33.
5. Powlson DS, Addiscott TM, Benjamin N, Cassman KG, de Kok TM, van Grinsven H, L’Hirondel JL, Avery AA, van Kessel C, “When does nitrate become a risk for humans?” Journal of Environmental Quality, 2008 Feb 11;37(2):291-5, Print 2008 Mar-Apr.
6. Forman D, Al-Dabbagh S, Doll R, “Nitrates, nitrites and gastric cancer in Great Britain,” Nature, 1985 Feb 21-27;313(6004):620-5.
This is all good, but I want an even more detailed scientific explanation...
...of how the body processes carbohydrates, ketones, etc., and I want it to be from an expert in their field, and I want it to include references to evidence that supports its conclusions
Okay, you asked for it: The metabolic effects of low-carbohydrate diets and incorporation into a biochemistry course written by Wendy Pogozelski, Professor of Biochemistry at SUNY Geneseo, NY. Click on that link and you can view the PDF for free. Very detailed, but to the point.
Scott Connelly, founder of Progenex, discusses various topics related to hyperglycemia and insulin. It’s a 90 minutes long “brain dump” that’s worth watching. WARNING: There are explicit scenes of a rat autopsy.
Low carb diets are all meat and cheese. You need fruit and vegetables to be healthy
These are a common fallacies. Low sugar fruits and vegetables are fine on a low carb regimen. Even the induction phase of the Atkins diet allows them. Secondly, the nutritional benefits and necessity of fruits and vegetables have been greatly exaggerated.
My vegan friend read this book called “The China Study” and it says...
Stop right there. “The China Study” has been used as justification by vegans and vegetarians for years. It posits that animal protein is harmful and plant protein is good based on a huge amount of data collected in China. To put it bluntly, it’s a crock. Denise Minger in her “Raw Food SOS” blog expertly picks it apart and shows how wrong it is.
Any other potential health benefits from a low carb diet?
Cancer
There’s a whole section in Good Calories, Bad Calories about the possible cancer risks carbohydrates can pose. Here’s an except from a recent interview:
I recently reported an article for Science on the mechanistic link that could explain why obesity and diabetes are associated with a higher risk of most cancers. And virtually everyone who studies this agrees that the link is insulin, or elevated levels of insulin known as hyperinsulinemia, and that insulin serves in a variety of ways to promote tumor growth and malignancy. I haven’t had time to write the story yet, and I won’t get into the dietary angle for Science because they prefer that I leave my own biases out of it, but two of the cancer researchers I interviewed – one at Harvard and one at Sloan-Kettering in New York – told me they fear that refined carbs and sugars are the primary or at least dietary cause of most human cancers. One of them said that refined carbs and sugars “scare him silly,” and the other said that he is effectively on the Atkins diet, not because he needs to lose weight, but because he doesn’t want to get cancer. I’m still trying to figure out what to do with this journalistically after I write the Science story, which I may not have time to do for another couple of months. - Gary Taubes
Epilepsy
From an interview by Dr. Richard Besser with the director of pediatric epilepsy at Massachusetts General Hospital, Dr. Elizabeth Thiele, Ketogentic Diet: How Can a High-Fat Diet Treat Epilepsy?
Besser: So this treatment is solely based on diet?
Thiele: This treatment is solely based on diet.
Besser: No medicines, nothing else?
Thiele: We do supplement vitamins, because with the high-fat, kids can become deficient in some vitamins -- so while on the diet, all children are supplemented with vitamins and also calcium.
Besser: So on this diet, some children, who are having dozens of seizures a day, will become seizure-free?
Thiele: We’ve had several children having hundreds of seizures per day become completely seizure-free, oftentimes within a few weeks.
Besser: So this is a treatment based solely on diet and vitamins?
Thiele: Absolutely. While on this treatment, hopefully, the children are taken off all of their medications if the diet successfully controls their seizures, and then they just continue on the diet for a period of time and supplement it with vitamins and calcium.
Besser: So on this you’ve seen children who’ve been having dozens of seizures a day become seizure-free?
Thiele: We’ve seen many children who are having hundred of seizures a day become seizure-free oftentimes within just a few weeks of being on the diet.
Besser: That’s miraculous.
Thiele: It’s miraculous. No, it’s a miracle. And many children who go on this diet have already been on six or eight or 10 anti-convulsion medications without effective seizure control or with side effects that can’t be tolerated. And they go on this diet and become seizure-free. About a third of children who go on this diet become completely seizure-free.
...
Besser: What kinds of things are being looked at for treatment with a ketogenic diet?
Thiele: Right now there’s some preliminary evidence in Parkinson’s disease and Alzheimer’s disease that a diet similar to the ketogenic diet may be very effective. And there’s actually a critical trial, ongoing, in ALS, or Lou Gehrig’s, disease of using a similar diet and there’s a lot of evidence, mainly animal model evidence, that similar diets may be very effective in helping to treat cancer.
Besser: Treating cancer?
Thiele: Treating cancer. There’s evidence in prostate cancer and there’s a lot of evidence in some brain cancers, like neuroblastoma. And I think that’s because cancer cells are rapidly dividing so they have a very high metabolic rate and they use a lot of energy.
And so the ketogenic diet basically shuts down the cell’s energy production and makes the cells rely more heavily on fat metabolism, and cancer cells, I think, are not thought to do that as effectively.
Here’s a video report by Dr. Besser on the topic of epilepsy treatment: Ketogenic Diet: How Can a High-Fat Diet Treat Epilepsy?
Should I worry about getting enough antioxidants in my diet?
From a recent interview with Gary Taubes:
Reactive oxygen species – the molecules we want antioxidants to fight – are created in large part by burning carbs (glucose) for fuel and so are a product of carb-rich diets. Eat fewer carbs and antioxidants in the diet become a moot issue.
My family/doctor/friends are telling me I’m going to get SICK and DIE on a low carb diet! HELP!
Print out this primer and give it to them. It’s more detailed than most diet books, if I do say so myself. Buy them a copy of the documentary, Fat Head on DVD. E-mail them this article: The misguided war on fat may be making us sicker. It’s an excellent summary of the issues and includes references to some of the latest research.
The USDA Guidelines say low fat diets are best and low carb diets may be dangerous. Can you provide a rebuttal?
Yes! An incredible paper was published in the October 2010 of Nutrition called In the face of contradictory evidence: Report of the Dietary Guidelines for Americans Committee that provides a detailed point-by-point rebuttal. The USDA’s stances on carbohydrates, protein, saturated fat, animal vs. plant, salt, diabetes, fiber and whole grains, and glycemic load/index are all examined and eviscerated.
In the three decades since [the original 1977 guidelines were released], carbohydrate consumption has increased; overall fat, saturated fat, and cholesterol consumption have decreased to near or below targeted levels; caloric intake remains within recommended levels; and leisure-time physical activity has increased slightly (pp. D1-1, D3-10, B2-3). At the same time, scientific evidence in favor of these recommendations remains inconclusive, and we must consider the possibility that the “potential for harmful effects” has in fact been realized. Notably, “the prevalence of overweight and obesity in the US has increased dramatically in the past three decades” (A4); the number of Americans diagnosed with T2D has tripled [81].
Laudable as the goals were, the application of those recommendations has constituted a population-wide dietary experiment that should be brought to a halt. Lack of supporting evidence limits the value of the proposed recommendations as guidance for the consumer or as the basis of public health policy. We ask whether the Dietary Guidelines for Americans process as it stands should continue or whether there might not be better alternatives.
I don’t have a scientific background, but I want to stay abreast of the latest health news
How do I know what articles are good and which are bad?
Check out this article by Dr. Alicia White called, How to read articles about health and health care. It contains questions to help you figure out which articles you’re going to believe and which you’re not.
You should also read this post by Chris Masterjohn called How a Study Can Show Something to Be True When It’s Completely False -- Regression to the Mean for some examples of statistical chicanery used in medical studies.
Any exercise advice?
There are other places that satisfy these kinds of questions, so no use repeating the info here. However, I would be remiss if I didn’t provide some general information. From the book, “The New Atkins for a New You”:
The body’s efficient use of dietary protein increases with exercise. Consuming enough protein combined with significant weight-bearing (resistance) activity, such as walking up and down stairs or lifting weights, can help preserve and tone your muscles during weight loss. With significant weight-bearing exercise, it may even be possible to add some lean body mass. In that case, you’re basically trading fat for muscle. The more you can preserve and tone muscle while losing fat, the better you’ll feel and look. [...] The added benefit of more muscle is that whether you’re working up a sweat or flopped on the sofa, you’ll still be burning more calories than someone at the same weight who has a greater percentage of body fat.
If you’re looking for a book that combines a low carb diet with exercise, this one comes recommended: S.P.E.E.D.
You can download the first chapter for free.
I wanna read “Good Calories, Bad Calories,” but it’s sooooo long. Waaaaaah!
Gary has a condensed and updated book called Why We Get Fat: And What to Do About It that is a lot quicker to get through.
There are a number of presentations by Gary Taubes available on the web. This one is the latest and most up to date: http://videomedia2.swedish.org/mediasite/SilverlightPlayer/Default.aspx?peid=cd8c7aa15bc94a0486f4ee9b66ef8f8f Why We Get Fat: Adiposity 101 and the Alternative Hypothesis of Obesity]. You need to install Silverlight to watch it.
Toban Wiebe outlined this groundbreaking book and posted it on his “Higher Thought” website: Complete Notes to Good Calories, Bad Calories. In case it disappears, TheCosmicMuffet reposted it on Google Docs for posterity.
Have there been any corrections or addendums for “Good Calories, Bad Calories” since it was published?
Yes. There have been recent discoveries regarding alpha glycerol phosphate that contradict what’s found in endocrinology and biochemistry textbooks. Glyceroneogenesis is a process where the body produces its own alpha glycerol phosphate. Even in a state of prolonged fasting, the body is able to use its own muscle protein to synthesize it. In other words, you can store fat without carbs. Technically, the information found in GCBC doesn’t conflict with these findings, but other articles and presentations Taubes has done will.
Acylation Stimulating Protein (ASP) is secreted by fat cells and allows fat to be removed from chylomicrons and stored in fat cells. ASP permits the body to store fat in the absence of insulin. However, insulin is overwhelmingly the most important driver of fat storage in vivo. Taubes never mentions ASP once.
So what’s the “TL;DR” advice?
“Diet > Exercise” and “Low Carb > Low Calorie.”
Changing your diet is more important than exercise. That doesn’t mean exercise is unimportant. It simply means you should give diet priority. Similarly, it’s more important to reduce your daily carb intake than calories. Carbohydrates raise insulin levels, which cause your body to store fat. Ironically, eating lots of fat doesn’t make you fat, nor does it make your cholesterol levels worse. (Trans-fats excluded.) Carbohydrates raise triglycerides, not high fat and high cholesterol foods.
Your goal should be to minimize your carbs as much as possible. In the beginning, I’d tell you to not even worry about calories. If you can get to about 50g of carbs a day, you will be in a position to lose weight quickly. I don’t know how easy/difficult it is for you to make these kinds of changes to your diet. Take a walk down the isles in your local supermarket and count the number of pre-packaged foods that are high in carbs and you’ll begin to realize what you’re up against. Carbs are cheap, so they’re plentiful.
As far as supplements, it’s up to you. If you eat low carb, you’ll be getting a lot of natural nutrients from your food. The two most important nutrients to combat insulin resistance and obesity are Vitamin D and Magnesium. However, increasing these nutrients will effect others, so you’ll need to add extra Vitamin A, Vitamin K2, and Calcium to the mix. I’d suggest taking fish oil for anyone (dieting or not) since the evidence of the effectiveness of omega 3 oils on health is starting to pile up. [Eggs are also a great source of omega 3, and each egg can have as much as a fish oil pill - Admin]
Do you NEED to do a low carb/high fat diet to lose weight? No. If you follow any diet strictly, you will probably lose weight (including lean muscle tissue). However, the low carb/high fat option has shown to be the most effective and most healthy option.
Links to other Low Carb resources
Blogs
- Livin’ La Vida Low Carb Blog & Podcast
- Low Carb Diets at About.com
- Fat Head
- Whole Health Source
- The Spark of Reason
- Dr. Mike Eades/Protein Power
- Free The Animal
- Hyperlipid
Articles
- Is Sugar Toxic? Gary Taubes weighs in on Robert Lustig's research on fructose.
- Dangers of fructose It doesn’t raise your blood sugar, but it’s still bad for you.
- Heart Attack Risk Reduction: The Low-Hanging Fruit The importance of Omega 3 Fats on heart health.
- Butter vs. Margarine Showdown Throw away that container of Parkay.
- Animal Models of Atherosclerosis: LDL Why animal models often fail to accurately model humans.
- How we’ve come to believe that overeating causes obesity An incredible article about the Minnesota Starvation Experiment. Proof positive that calorie restriction is not a realistic diet. (FYI, this was a “starvation” diet of 1,600 calories a day including exercise. Compare that to other popular calorie restricted diet plans that are being passed off as healthy, today.
- Bad cholesterol: It’s not what you think Excellent summary of the fat and cholesterol myths.
- The Great Cholesterol Myth Great explanation of the “Lipid Hypothesis,” how it became so prevalent, and why it’s wrong.
Video
- Tom Naughton’s Big Fat Fiasco ” is on YouTube, but you can buy it on DVD, too.
- Fat Head: Have you seen the news stories about the obesity epidemic? Did you see Super Size Me? Then guess what ... You’ve been fed a load of bologna. Comedian and former health writer Tom Naughton replies to the Super Size Me crowd by losing weight on a fat-laden fast-food diet including plenty of double quarter-pounders and fried chicken while demonstrating that nearly everything we’ve been told about obesity and healthy eating is wrong. Fat Head features humorous animations as well as informative interviews with doctors, nutritionists, and political scientists.
- My Big, Fat Diet: The Namgis First Nation of Alert Bay gives up sugar and junk food, returning to a traditional style of eating for a year to fight obesity and diabetes.
- Sugar: The Bitter Truth: Robert H. Lustig, MD, UCSF Professor of Pediatrics in the Division of Endocrinology, explores the damage caused by sugary foods. He argues that fructose (too much) and fiber (not enough) appear to be cornerstones of the obesity epidemic through their effects on insulin.