When I developed diabetes in 1946, physicians thought that the high illness and death rate of diabetics was due to dietary fat and the supposedly resultant elevation of serum cholesterol. Since the DCCT trial, the scientific literature overwhelmingly supports the role of elevated blood sugar in all long-term diabetic complications.
Yet even today, many physicians ignore the need for normal blood sugars and focus on dietary fat. The 2006 Clinical Practice Recommendations (1) of the ADA advocate large amounts of dietary carbohydrate (45 – 65% of total calories) and small amounts of protein and fat. This recommendation is preceded by the statement that "dietary carbohydrate is the major contributor to postprandial (after meal) glucose concentration."
The high carbohydrate load is justified by the claim that "the brain and central nervous system have an absolute requirement for glucose as an energy source." This statement, while only partially correct (ketones from stored fat keep the brain alive during starvation), ignores the fact that in the absence of dietary carbohydrate, the liver, intestines, and kidneys convert dietary protein into as much glucose as the brain requires.
Virtually the entire evolution of mankind occurred when our ancestors were hunter-gatherers, well before the inventions of agriculture and animal husbandry. (2) These people had scarcely any access to dietary carbohydrate and certainly no access to animal milk, cereal grains, whole-grain and refined breads, refined sugars, and sweet fruits. They ate almost exclusively lean meat and fish, plus small amounts of leafy and other low carbohydrate vegetables. Some humans, such as Eskimos, consumed only fat and protein. Our pre-agriculture ancestors frequently had violent deaths, but no coronary, kidney, or arterial disease, no tooth decay, and no diabetes.
By 1969, when I first began to measure my own blood sugars, I was already suffering from about 15 major and minor long-term complications of diabetes, thanks to the low fat, high carbohydrate diet I had been following for 23 years. By about this time, scientific studies of animals had demonstrated the prevention and even reversal of many diabetic complications by blood sugar normalization.
I soon discovered that even multiple daily insulin injections (basal/bolus dosing) would not achieve anything close to steady normal blood sugars. It was not until I lowered my carbohydrate consumption to a daily total of 30 grams (mostly from leafy and cruciferous vegetables) that things fell into place. Today my A1c is 4.5% (normal is 4.2-4.6%), and my target blood sugar is 83 mg/dl (about mid-normal for young non-diabetic adults).
Most of my long-term complications, including advanced kidney disease and severe gastroparesis, have normalized. Those that involved irreversible muscle loss (droopy eyelids, intrinsic minus feet (diabetic foot)) have not gotten worse. My lipid profile, which had been grossly abnormal, now shows: Triglycerides–50; LDL–53; HDL–118; and LDL subparticles – Type A. I see similar results in others who follow a prehistoric diet like my own (except for some type 1's with severe gastroparesis).
Until very recently, researchers were not comparing the effects of low carbohydrate diets to the ADA low fat/low protein diet. Recent results consistently support low carbohydrate, high protein¬ diets–not only for blood sugar control, but also with regard to weight loss and cardiac risk. Many of these studies are posted on the Web site of the Nutrition and Metabolism Society, at nutritionandmetabolism.com.
I am not alone. Thousands of type 1 and type 2 diabetics are following very low carbohydrate diets. Many observe that both fat and protein bring about satiety, while carbohydrate leaves them hungry and craving more carbohydrate. Other studies have focused on the importance of dietary protein for prevention of bone loss (4) and for preventing blood pressure elevation (5).
Richard K. Bernstein, M.D.,
F.A.C.E., F.A.C.N., F.C.C.W.S.
Mamaroneck, NY 10543
1. Amer Diabetes Assoc Clinical Practice Recommendations, Diabetes Care, Vol 29 Suppl 1, Jan 2006, p. 513
2. Cordain et al, Origins and Evolution of the Western Diet: Health Implications for the 21st Century, Amer J Clin Nutr; 81:341-54, 2005
3. Science, 307:840, Feb 2005
4. Bonjour J-P, Dietary Protein: An Essential Nutrient Factor for Bone Health, Jnl. Amer. Coll. Nutrition 24:6, 5265-5365, 2005
5. Obarzanek et al, Dietary Protein and Blood Pressure, JAMA 275:20, 1598-1603, May 1996
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