August 2003

Vol. 2     No. 8  

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Suck Carrots, High Protein Diet Advocates

Promoters of high protein diets discount the importance of traditional risk factors, such as elevated blood cholesterol, because they do not fit well into their backwards theories on diet, health, and weight loss.  Support for their diatribe is also provided by papers written in scientific journals suggesting that half of the people suffering from coronary heart disease do not have the conventional risk factors.  Instead they propose risk factors that fit better with the teachings found in their diet books, such as elevated insulin levels, to be the most relevant predictor of heart disease.  The Zone diet is a good example of this kind of diversion.

This week’s issue of the Journal of the American Medical Association, with three lead articles and an accompanying editorial, clearly shows that consumption of the standard American diet, and the resulting elevation of traditional risk factors, accounts for the vast majority of heart disease.1-4  Two separate articles examined data from 122,458 people in 14 randomized clinical trials and 386,915 people in 3 observational studies to challenge the claims that 50% of heart patients lack the conventional risk factors.1,2

Six Conventional Risk Factors

1)  Elevated Blood Cholesterol (> 200 mg/dl)

2)  Elevated Blood Pressure (> 140/90 mm/Hg)

3)  Diabetes

4)  Obesity

5)  Adverse Dietary Habits

6)  Cigarette Smoking

The solution is much less confusing than having to worry about 6 separate problems (risk factors). The first four risk factors are a direct consequence of the fifth (adverse dietary habits).  The risk factor of cigarette smoking also reflects an unhealthy diet.  Smokers have a higher intake of total fat, saturated fat, and cholesterol, and a lower intake of folate, vitamin C, beta-carotene, and fiber than nonsmokers.5,6  In other words, smokers consume significantly more meat, dairy products, and processed foods; and fewer fruits and vegetables, than nonsmokers.  As a result, smokers have a much less healthy diet than nonsmokers and this may be the most important reason why they have more heart disease, rather than the direct toxic effects from cigarette smoke. (Of course, smoking is bad for you too.)

Between 89% and 100% of the time, fatal heart disease was found to be associated with at least one of the above risk factors.  In 75% of cases of non-fatal heart disease, total cholesterol was equal to or greater than 200 mg/dl.  Other risk factors – like C-reactive protein (CRP), homocysteine, Lp(a) and fibrinogen –  have caused people to be distracted from the real issue of diet, and cannot be recommended over traditional risk factors for use in predicting risk of heart disease.3

Unfortunately, most patients and doctors will take from this journal a message to redouble their efforts to stamp down (out) risk factors by prescribing even more medications for blood pressure, cholesterol, diabetes and obesity.4  Real benefits from this drug approach are limited and/or of questionable value.  The simple reason for this is because people do not die from risk factors – I have never seen a patient die of high blood pressure, high blood sugar, high cholesterol or obesity.  People with these signs of disease die of rotten arteries in their heads and hearts. – strokes and heart attacks.  So why not go to the source of the trouble? The real solution to these problems is to correct the underlying causes – the adverse diet primarily, and secondarily the lifestyle issues (exercise, smoking, coffee, etc.)  Unfortunately, there is little profit in this approach.  Besides, too many people see taking a pill to be much easier than giving up beefsteaks and ice cream sundaes.  But they are dead wrong.


1)  Khot UN.  Prevalence of conventional risk factors in patients with coronary heart disease.  JAMA 2003; 290:898-904.

2)  Greenland P.  Major risk factors as antecedents of fatal and nonfatal coronary heart disease events.  JAMA 2003; 290:891-897.

3)  Kackam D.  Emerging risk factors for atherosclerotic vascular disease.  A critical review of the evidence.  JAMA 2003; 290: 932-940.

4)  Canto CG.  Major risk factors for cardiovascular disease. Debunking the “only 50%” myth. JAMA 2003; 290:947949.

5)  Palaniappan U. Fruit and vegetable consumption is lower and saturated fat intake is higher among Canadians reporting smoking. J Nutr. 2001 Jul;131(7):1952-8. 

6) Dallongeville J. Cigarette smoking is associated with unhealthy patterns of nutrient intake: a meta-analysis. J Nutr. 1998 Sep;128(9):1450-7. 

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