THE PRUDENT DIET - IT DOES MAKE SENSE

(November 2001)

A recent issue of the American Journal of Clinical Nutrition has a very interesting and instructive article on dietary patterns and risk of coronary heart disease. It is based on a followup study of 44,875 men ages 40 to 75 years. During the followup period, there were 1,089 fatal and non-fatal heart attacks. The men were divided into two groups based on dietary histories.

Then the strength of adherence to each diet was determined by dividing the group (prudent or western) into five categories (quintiles) from least to most adherence. As adherence to the prudent diet increased, the risk of heart attack decreased. In the group with greatest adherence, the risk was reduced by 34 percent, a statistically significant decrease.

In contrast, the more men followed the western diet, the greater the risk of heart attack, rising to a 64 percent increased risk in those most strongly following that dietary pattern.

The authors concluded "this study provides strong evidence that a diet high in vegetables, fruit, legumes, whole grains, fish, and poultry and low in red meat, processed meat, high-fat dairy products, and refined grains may reduce the risk of coronary heart disease".

Commentary: This study makes it pretty simple. The more you follow the "prudent" diet, the less likely you are to suffer a heart attack. On the other hand, the more you adopt the "western" diet, the greater your risk of heart attack.

There are some issues:

The authors could not separate lean cuts of red meats from cuts with more fat. Lean cuts actually belong more to the prudent diet than to the western diet.

There is one problem with the study that should be noted. With the prudent diet, the men who followed it more consistently smoked less, used more vitamins, took more vitamin E supplements, and engaged in more physical activity. In contrast, the more men followed the western diet, the more they smoked, the less they used vitamins, the less they used vitamin E supplements, and the less they engaged in physical activity. Thus, the prudent and western diet groups were different in many respects. The authors attempted to take these differences into account; whether they fully succeeded is not certain.

In general, this dietary prescription makes a lot of sense, but it is still crucial to realize that the major risk factors for coronary heart disease and heart attacks are high cholesterol, high blood pressure, and smoking. Following the western diet instead of the prudent diet accounts for only a modest amount of the coronary heart disease risk, whereas smoking, cholesterol, and blood pressure account for 60 to 70 percent of the modifiable risk. The best way to reduce the risk of coronary heart disease and heart attacks is to keep cholesterol levels low (below 200 milligrams per deciliter), keep blood pressure in the low normal range, and not smoke.

Still, the prudent diet makes a lot of sense; it probably works in part by lowering cholesterol levels.. You do not have to be rigid about it - just be sure to have its dietary items as a major portion of your daily diet.

Hu, F., et al. Prospective study of major dietary patterns and risk of coronary heart disease in men. American Journal of Clinical Nutrition. Vol 72. (October) Pgs 912-921. 2000.