lipid hypothesisTag 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.