high-carbohydrate dietTag Archives

The diabetes, heart disease, and the lipid hypothesis

It boggles my mind that high-carbohydrate diets are recommended to diabetics even though the carbohydrates will increase their insulin needs. The recommendations come out of a faulty belief in the lipid hypothesis. The intent is to prevent the heart disease that often accompanies diabetes. Those on the lipid hypothesis bandwagon like to cite Ancel Keys, but his study fell apart when confounding factors such as accuracy of the reporting of cause of death country to country were looked at. High- carbohydrate diets do lower cholesterol. I can even attest to that from my own experience with the vegan diet. But more recent studies are showing that there is no clear relationship between cholesterol and heart disease. T. Colin Campbell could not find one in his extensive study of the Chinese, and he very much would have liked to since it would have supported his assertion that a vegan diet is healthier. Never mind that the vegans were dying of infectious diseases and malnutrition at a higher rate.

Have you noticed that guidelines relating to cholesterol have been changing? It used to be that they told us that all cholesterol was bad. Then they told us that HDL was a good cholesterol and needed to be high and LDL was the bad cholesterol. Now they’re telling us that not all LDL is bad. It’s only the small dense LDL that’s bad. Such a change over the years! By the way, a high-carbohydrate diet increases the harmful small dense LDL. Some studies do show that heart disease improves when cholesterol is lowered by cholesterol drugs. But there may be another effect at work. The American Heart Association published a study showing that statins decrease inflammation, and this effect may actually be the beneficial action of the drugs.

With the lipid hypothesis falling apart, the rationale for recommending a low-fat/high-carbohydrate diet to diabetics falls by the wayside, or at least it should. Doctors who have suggested anything else have lost their jobs even though their results have proved their recommendations to be valid. So there’s a disincentive in the industry for jumping off the high-carbohydrate bandwagon even if it might actually be wrong. Many doctors are frustrated by the lack of improvement in their diabetic patients, but they’re also afraid to stray from the standard recommendations. A high-carbohydrate diet increases the need for insulin, which is a dangerous situation for a diabetic. Plus, as mentioned, it increases the worst kind of cholesterol. It’s far better to pursue a diet that decreases the need for insulin, I think.

Triglycerides have been shown to be more strongly linked to heart disease than cholesterol is. A high-carbohydrate diet increases triglycerides, too. If you are trying to prevent heart disease and diabetes, a closer look is definitely warranted. The standard protocol may not be the best one.

The positive correlation of wheat to heart disease proved to be interesting. Wheat has a correlation of 0.67 with heart disease—which is the strongest association between any food and heart disease found in the China Study. This is of particular concern given that the recommended high-carbohydrate diet often contains a lot of wheat. I picked the correlation out of a table from a post on animal protein, but apparently I was not the only one to notice. The blogger, Denise Minger, did an entire post on that correlation elsewhere in the blog. She took the data from China Study II and attempted to determine if the wheat/heart disease correlation was confounded by any other factors. With every combination she tried, the wheat/heart disease correlation held up. T. Colin Campbell, an author of China Study II, wrote a paper on the link back in 1996. The theory is that the correlation has something to do with the insulin index of wheat compared to rice. The insulin index of the rice is quite low compared to its glycemic index while the insulin index of wheat is high. In other words, wheat stimulates a higher output of insulin than rice does. I took a look at a chart listing the insulin scores of foods compared with their glucose scores. Rice did indeed have an insulin score much lower than its glucose score, both for brown rice and for white rice, which made it rather unique among carbohydrate sources on the list.

Denise Minger looked through the literature to see if there were any research studies relating to wheat and heart disease. Apparently, there were very few. It isn’t something researchers are looking at. Most wheat related research looked at things like whole grain vs. processed grain. She did find an old rabbit study that looked at wheat germ vs. various oils and atherosclerosis and a human study that looked at wheat bran vs. flaxseed and insulin sensitivity and C-reactive protein. In both studies, the wheat group fared worst. The wheat connection is definitely something that deserves a closer look. Hopefully, other scientists picked up on it and will do some studies.

It would not surprise me if the link held up under closer scrutiny. Gluten, a protein in wheat, has already been found to cause problems in relation to other disorders. I am at present trying to get my daughter to try a gluten free diet to see if it will help improve her neuropathy. The doctors think now that the neuropathy is a rare autoimmune reaction related to her cancer. Supposedly, gluten-free diets have improved neuropathy. Gluten-free diets have been shown to help other autoimmune disorders as well.

References:
T. Colin Campbell. The China Study: The Most Comprehensive Study of Nutrition Ever Conducted And the Startling Implications for Diet, Weight Loss, And Long-term Health. BenBella Books (May 11, 2006).
Denise Minger. “Forks Over Knives”: Is the Science Legit? (A Review and Critique), Raw Food SOS.
Denise Minger. The Truth About Ancel Keys: We’ve All Got It Wrong, Raw Food SOS.
Denise Minger. The China Study: My Response to Campbell, Raw Food SOS.
Denise Minger. Heart Disease and the China Study, Post #1.5, Raw Food SOS.
David J. Lefer, PhD. Statins as Potent Antiinflammatory Drugs, Circulation 2002; 106: 2041-2042, American Heart Association.

Theory behind the Rosedale Diet

I’ve read the main part of the theory behind Dr. Rosedale’s diet in his book and some of the practical application. What follows is my summary of that information.

Dr. Rosedale says that the body can burn fat or sugar, but it won’t burn both at the same time. He claims that a diet high in carbohydrates causes the body to get stuck in sugar burning mode. When there is too much sugar in the blood, the excess gets stored as saturated fat. That would be fine if we could then switch to fat burning mode and burn the fat when the sugar is used up. But that, Dr. Rosedale claims, is not what happens. As we get older, our ability to switch between sugar burning mode and fat burning mode diminishes. So when someone in sugar burning mode runs out of sugar to burn, his body cannibalizes the protein from its muscle and bone to make sugar to burn. The fat remains in the fat cells. This is why someone who loses weight on a typical low-fat/high-carb diet loses muscle and ends up being a smaller version of a fat person.

A low-carb/high-protein diet does not correct this problem since excess protein in the diet is converted into sugar, and that raises blood sugar, too, and the body ends up remaining in sugar burning mode. The body does not store protein, so the body still ends up cannibalizing muscle and bone when the supply of sugar and dietary protein runs out. When protein is converted to sugar, the nitrogen atoms are stripped from the protein in the form of urea and ammonia, and this becomes a toxic waste product that the body must deal with. So really, a diet that includes excess protein is toxic. Dr. Rosedale recommends getting 50 – 75 grams of protein from the diet, which is consistent with RDA recommendations.

So that leaves fat as a preferred source of fuel. But not all fats are healthy. Dr. Rosedale recommends getting fat from fish and fish oil, nuts and nut oils, avocados and avocado oil, olives and olive oil, and coconut oil. He recommends eating lean poultry, limited amounts of lean meat, and low-fat dairy from properly raised animals to avoid the saturated fat content. Properly raised animals means grass-fed or pasture-raised and animals raised without added hormones and antibiotics, not the CAFO animals typically sold in supermarkets. The diet also includes generous amounts of non-starchy vegetables and some berries.

As an aside, Dr. Rosedale did mention the link between depression and low-fat diets, which has been my primary contention against them and why I have increased the fat in my NutriSystem plan, having myself suffered from depression that I now believe was a result of low-fat dieting.

Dr. Rosedale also claims that his diet is de-aging. The low-carb content of his diet gives the life-extension benefits of a calorie-restricted diet without having to go hungry. In other words, he is claiming that his diet can reverse age-related degeneration. This is due to the low insulin and leptin levels maintained while on such a diet and the proper functioning of these hormones. Dr. Rosedale’s diet is a lifestyle diet. His list of benefits from his diet is quite long, and there isn’t space to list them all here.

The general theory behind Dr. Rosedale’s diet makes sense to me and agrees with my experience of dieting. I have lost weight on a high-fat diet before. I also believe that I have suffered harm from low-fat diets as Dr. Rosedale says we will, namely my worst depressions have coincided with stints of low-fat dieting. Dr. Rosedale’s theories also explain a lot about why we yo-yo and how fat can end up in the arteries, among other effects that can result from the derangement of insulin and leptin functioning. I’m not sure about Dr. Rosedale’s recommendation to minimize animal fat. I do agree that ideally the animals should be pasture-raised if one can afford to buy such since grain feeding alters the balance of the polyunsaturated oils from healthy omega-3 to harmful omega-6. But I also have been led to believe that animal fat contains important fat-soluble nutrients that are difficult to get from other sources. Therefore, meats and dairy should include their fats. My previous foray into veganism and subsequent detriment would support this conclusion.

An interesting dietary study from 1931

There was an interesting dietary study done in 1931. They conducted a controlled dietary trial using a large variety of diets, ranging from 800 to 2,700 calories. Before they did that, they put all patients on a 1,000 calorie diet of varying types. Here are the stats for the average daily losses for the 1,000 calorie diets:

High-carbohydrate/low-fat – 49 grams
High-carbohydrate/low-protein – 122 grams
Low-carbohydrate/high-protein – 183 grams
Low-carbohydrate/high-fat – 205 grams

In other words, the patients on the low-carbohydrate/high-fat diet lost 4 times what those on the high-carbohydrate/low-fat diet lost. In another commentary on this diet, Barry Groves said that some patients actually gained weight on the high-carbohydrate/low-fat diet.

It was expected that on the 1,700 and 2,700 calorie diets, patients would not lose weight. In fact, all but three did lose weight.

In their conclusion, Lyon and Dunlop said: “The most striking feature … is that the losses appear to be inversely proportionate to the carbohydrate content of the food. Where the carbohydrate intake is low the rate of loss in weight is greater and conversely.”

Barry Groves says in Trick and Treat that the high-fat diet is preferable over the high-protein diet because excess protein creates waste products that stress the organs such as the kidneys. Fat burns cleaner in the body.

References:
Lyon DM, Dunlop DM. The treatment of obesity: a comparison of the effects of diet and of thyroid extract. Quart J Med 1932; 1: 331.
Barry Groves. Trick And Treat – how ‘healthy eating’ is making us ill. 2008.
Barry Groves’ site: http://www.second-opinions.co.uk/

High-fat diet best for weight loss

There was a study done in 1956 comparing weight loss on diets of differing macronutrient content. The diets were all 1,000 calories. One was 90% carbohydrate, another was 90% protein, another was 90% fat, with the last being a mixed diet. Those on the 90% fat diet lost the most weight, with those on the 90% protein diet coming in as a close second. Those on the 90% carbohydrate diet lost the least, and some of those even gained weight.

Reference:
A. Kekwick M.A., M.B. Camb., F.R.C.P. , G.L.S. Pawan B.Sc. Lond. Calorie intake in relation to body-weight changes in the obese. The Lancet, Volume 268, Issue 6935, Pages 155 – 161, 28 July 1956.