Some even claim that ketosis, the subsequent pre-acidotic condition induced by severely limiting (or avoiding) carbohydrate intake, is a desirable health-supportive condition. (Strange - to suggest that a condition inherent to disease is a plus for wellness when induced by diet is, at best, bewildering). In my opinion, however, the most controversial claim from Dr. Robert Atkins et al is that diets deriving calories almost exclusively from meats, cheeses, and eggs – foods high in saturated fat and cholesterol – improve blood lipid profiles. The idea, of course, is that the body overreacts – positively - from excesses of dietary taboos (fat and cholesterol), inhibiting the synthesis of cholesterol in the liver (the major source of serum cholesterol). Sounds almost homeopathy-like, distantly similar to Samuel Hanneman’s Law of Similars – a notion that symptoms of disease can be cured by extremely small amounts of substances that produce similar symptoms in healthy people when administered in large amounts (like developing immunity to snake bite by injecting small amounts of venom; or, recovering from a hang-over by having a Bloody Mary for breakfast). Where high-protein diets depart from homeopathic principles, however, is in amounts consumed. Homeopathy purports highly diluted formulations – the smaller the better (i.e. Law of Infintesimals). High-protein diets, to the contrary, have no established ceilings for lipid intake.

Opposing the high-protein tidal wave is the conservative scientific minority (American Dietetic Assn., American Heart Assn., U.S. Government, Center for Science in the Public Interest, etc.) who refer to reams of research over the past 50 years indicting saturated fat and cholesterol as the primary causes of CAD (coronary artery disease) and, possibly, some cancers. Could doing something as simple as pulling the plug on carbs (bunless burgers without fries) reverse the process?

In a one-year study conducted by the Fleming Heart and Health Institute and Camelot Foundation (Omaha, Nebraska), 26 volunteers were periodically evaluated for multiple risk factors {cholesterol, triglycerides, homocysteine, Lp(a) [i.e. Lipoprotein (a) - The resultant molecule formed when protein made from the apo(a) gene combines with LDL. High levels of Lp(a) increase the risk of developing coronary disease.], fibrinogen (a blood protein that when excessive reduces blood flow and increase the risk of clots), antioxidants, endothelial dysfunction (a reduced ability of cells lining blood vessels – endothelial – to produce nitric oxide, a gas which mediates vasodilation. A large number of risk factors for atherosclerosis including hypercholesterolemia, systemic hypertension, smoking and diabetes have been associated with this condition.), inflammation, infection, dietary factors} and progression of CAD1. Ten of the 26 participants opted for a high-protein diet whereas the other 16 consumed a more traditional heart disease diet. Since the participants (patients) were at risk, standard medical and lifestyle strategies were utilized in the treatment of risk factors. At the end of the study, patients following the prescribed diet enjoyed a decrease in all the independent risk factors, viable myocardium (well-functioning heart muscle) being restored in 44% of the myocardial segments observed. Those opting for a high-protein diet worsened in all risk factors and had an overall 40% increase in CAD progression. In particular, the high-protein group had increases in fibrinogen, Lp(a), and C-RP (a test for inflammation) of 14%, 106%, and 61%, respectively. The differences between progression and extension of disease (in the high-protein group) compared to the regression of disease (in the group following the prescribed diet) were very highly significant (p<0.001).

Realistically, some criticisms of this study are valid - the small group sizes (16 and 10), for instance, or possible biasing via confounding between medical intervention and diet. I’m sure Dr. Fleming (the study’s lead researcher) would agree and welcome more research. However, the fact that differences observed between the two groups was very highly significant (only 1 chance in 1000 that the results could have happened by chance alone; number of volunteers being an inherent part of the analysis) would at least challenge the efficacy of high-protein diets by those being treated for CAD.

Bottom Line
If you are under the care of a cardiologist and are being treated for CAD risk factors, avoid high-protein diets. Instead, opt for the recommendations of the American Heart Association or a Registered Dietician. In severe cases, consider one of the proven low-fat vegetarian (or near-vegetarian) dietary/holistic programs as advocated by Dr. Dean Ornish, Pritikin Centers, Dr. John McDougall, etc.

1Fleming, RM. 2000. The effect of high-protein diets on coronary blood flow. Angiology 2000 Oct;51(10):817-26

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