Heart Disease
A plethora of information exists about heart disease. For many years we’ve heard about the “low fat, low cholesterol, low sodium diet.” However, this type of eating has not shown to be the cure-all it was once thought. In the last several years, I have had the privilege of hearing Dr. Walter Willett give several lectures. The most intriguing lecture I heard him give was called “Prevention of Heart Disease: How we’ve misled the Nation.” Dr.Willett is one of the world’s leading nutritional epidemiologists from Harvard.
The basic take home message of the lecture conveyed how the low fat, high carbohydrate diet has caused heart disease to increase. It is well known that eating a very low fat diet can increase one’s triglyceride levels (part of the cholesterol panel) and decrease the HDL cholesterol (the good or “happy” cholesterol as I refer to it). Dr. Willett stated that when one needs consumes a balanced diet with protein at each meal, moderate amounts of carbohydrate, and “good” or monounsaturated and polyunsaturated fat, heart disease can dramatically decrease. Having adequate amounts of monounsaturated fat in the diet can assist with lowering triglyceride levels and increasing HDL cholesterol levels. Foods which contain monounsaturated fat are avocados, nuts, and olive oil. Historically many people avoid these foods due to their fat content. The current research shows that these foods help prevent heart disease by how they change the lipid/cholesterol profile in the blood. Besides helping to prevent heart disease, healthy fats are important for proper digestion and absorption, healthy skin and hair, and absorption of fat-soluble vitamins.
Another important point Dr. Willett made is that it is not cholesterol in the diet that increases cholesterol in the blood. Foods that can increase cholesterol include saturated and trans fat, and too much carbohydrate. Dr. Willett states, “there has never been a study showing that eggs increase cholesterol.” Eggs contain a lot of cholesterol, but only 1 gram of saturated fat. Therefore, the current guideline of avoiding eggs or limiting eggs to 3 per week has no real scientific basis. It was just assumed by many health organizations that cholesterol in the diet automatically increases cholesterol in the blood. However, over the past several years it is clear that other things are responsible for increasing one’s cholesterol. A study published in the American Journal of Clinical Nutrition in March of 1999 showed that when men carry genes for heart disease they can actually make more LDL (or bad) cholesterol when they go on a low-fat diet. Dr. Stampfer of the Harvard School of Public Health states “the nutrition community has pushed this notion that fat equals bad without making distinctions between the types of fat. Our message to the public needs to be to replace saturated and trans fat with polyunsaturated and monounsaturated fats.” When the men from this study changed the fat in their diet from saturated to unsaturated fats they had a drop in LDL (the bad) cholesterol.
Therefore, eating a balanced diet with enough lean protein, moderate amounts of carbohydrate and monounsaturated and polyunsaturated fats can go a long way towards health and heart disease prevention. The idea that one diet fits all is far from the truth and each person’s particular health history needs to be taken into account for a good diet prescription.
Copyright 2010 Susan B. Dopart, M.S., R.D.
