Diet Still at the Heart of Preventing Cardiovascular Risk

Before I present the above-titled article, I want to point out that the diet that has assisted me to full healing from IBS, chemical sensitivities, chronic bladder and yeast infections, and a host of other ailments is most similar to a high-protein diet, which in the following studies shows great benefit toward cardiovascular health. My diet is also different than the well-known high-protein diets in many significant ways.

Reprinted with permission from the supplement company Ortho Molecular.

Most of the readers of the Validus use dietary supplements in their practice to help augment the health of their patients by preventing or treating adverse health outcomes. Unfortunately, much of the increased risk that patients experience is directly caused by unhealthy lifestyle and diet choices they have made (and continue to make). Add to this the confusion over the "science" of healthy eating over the past several decades and the result is an epidemic of obesity and metabolic syndrome, leading to dramatically increased risk for cardiovascular disease and diabetes. This issue reviews a few new studies looking at various diets and their effects on cardiovascular risk markers in obese patients.

Many diets and dietary models have been promoted over the years, and now many of these are being studied for their effectiveness in weight management as well as other important measurable risk factors. The ongoing debate between a low carbohydrate vs. a low fat diet and the effects of a low-glycemic load (GL) diet has been the focus of recent research. A group at Boston ’s Children’s Hospital evaluated the effects of a low-glycemic load diet (ad-libitum access to low glycemic carbohydrates), to a conventional low-fat diet (55-60% energy from carb. <30 from fat) on cardiovascular risk factors in obese young adults. While the low-fat diet was designed to produce a calorie restriction (250-500 kcal/day) the experimental low-GL diet was not calorie restricted. While the amount of weight loss, fat mass, lean mass changes were not significantly different between the groups, significant differences were seen in several meaningful cardiovascular risk factors! Subjects consuming the low-GL diet had significantly lower triglycerides and a strong, although not statistically significant increase in HDL cholesterol (+12.2 % vs. +1.1 % P=.08). The largest measurable difference was the dramatic decrease (-39%) of plasminogen activator inhibitor 1 (PAI-1, an independent risk factor for cardiovascular events which inhibits fibrinolytic activity) in the low-GL group compared to an increase (+33.1%) in the conventional diet group. [PubMed]

In a similar study [PubMed] comparing cardiovascular risk and nutritional status in obese women consuming either an experimental low fat (20%)/higher carbohydrate (61%) diet or a high protein (31%) diet, researchers again noticed no statistical difference in weight loss between the two groups (except in subjects with high triglyceride levels- the high protein diet produced nearly a 25% greater weight loss (P=0.005)). Triglyceride reduction was also significantly lower in the high protein diet subjects. Taken together with the previous (and other similar studies) it seems that obese individuals with insulin resistance and/or high triglycerides would benefit both in weight loss and risk factor reduction by increasing protein intake and adjusting carbohydrate intake by consuming low-glycemic index carbohydrates.

1. Effect of a high-protein, energy-restricted diet on body composition, glycemic control, and lipid concentrations in overweight and obese hyperinsulinemic men and women. Am J Clin Nutr. 2003 Jul;78(1):31-9.

2. Carbohydrate-restricted diets high in either monounsaturated fat or protein are equally effective at promoting fat loss and improving blood lipids. Am J Clin Nutr. 2005 Apr;81(4):762-72.

3. Comparison of high-fat and high-protein diets with a high-carbohydrate diet in insulin-resistant obese women. Diabetologia. 2005 Jan;48(1):8-16.

4. Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutr Metab (Lond). 2004 Nov 8;1(1):13.