Nutrition & Health   > Guide to Healthy Eating Questions & Answers


Physicians Committee for Responsible Medicine (PCRM) -- P.O. Box 96736 -- Washington, D.C. 20077-7541


A healthy person is a blessing on animals. Most sicknesses in western society are cured with drugs made from animals, and/or tested on animals, by the doctors who very likely have acquired their skills by experimenting on lab-animals. Under the circumstances, a compassionate vegetarian must learn how to remain healthy.


Reducing Cholesterol Levels


Q. I have been following a diet recommended by my doctor to lower my cholesterol. It is a 30 percent fat diet with no more than 300 milligrams of cholesterol a day. The diet helped to reduce my cholesterol from 250 to 220. I think that it is still too high, but I can't seem to get it any lower. I've read that adding polyunsaturated fats to my diet, such as vegetable oils, helps to lower cholesterol. Do you think that this would help me? I'd like my cholesterol to be below 200.


There are a number of changes you can make in your diet to lower your cholesterol further, but adding more vegetable fat isn't one of them.


Since saturated fat raises cholesterol more than anything else in the diet, replacing saturated fat with unsaturated fat will help to lower cholesterol. However, the best diet for lowering cholesterol levels is to reduce all the fat in your diet. The reason for this is that most fat is a combination of saturated and unsaturated fats. Animal products and some vegetable fats such as coconut oil and chocolate are very high in saturated fat. And while most vegetable oils are higher in polyunsaturated fat, all vegetable oils do contain some saturated fat. If you consume significant amounts of these oils, the amount of saturated fat in your diet begins to creep up.


Some scientists believe that our blood cholesterol levels should be below 150. Most people cannot achieve this optimal level of cholesterol on a 30 percent fat diet. A diet that is 30 percent fat will result in some reduction in blood cholesterol levels, but by lowering your fat intake more, you can achieve much better results. To achieve a significant decrease in your cholesterol it is probably necessary to reduce fat intake to between 10 and 20 percent of your calories. That means that for every 1,000 calories you eat, you should consume no more than 11 to 22 grams of fat. Since saturated fat and cholesterol both raise blood cholesterol levels, it is best to keep them both as low as possible in your diet. Saturated fat is found primarily in animal products, coconut oil, palm kernel oil, and chocolate. Cholesterol is found only in animal products. This may be one reason why vegetarians have lower blood cholesterol levels than people who eat meat.


HDL and LDL Cholesterols


Q. I have never been very worried about my blood cholesterol level since it has always been between 140 and 150. The last time I went to the doctor, however, he told me that my HDL cholesterol was 32 and that this was too low. Why is it bad for some kinds of cholesterol to be low? What type of diet will raise my HDL cholesterol?


The cholesterol in your blood stream is ferried around by compounds made of fat and protein, called lipoproteins. There are several different kinds of lipoproteins and each has different functions in the blood. High Density Lipoproteins, or HDLs, remove cholesterol from the tissues of your body and take it to the lever to be degraded. They also might protect against the development of atherosclerosis in other ways. Therefore, a higher level of HDL-cholesterol, which is commonly referred to as "good cholesterol," is associated with a lower risk of heart disease. Low Density Lipoproteins, or LDLs, carry cholesterol to the body tissues. Elevated levels of LDLs are associated with higher risk of heart disease. The best case scenario is a high HDL level relative to the LDL level.


HDLs can be low for a number of reasons. To a certain extent they tend to be controlled by genetics. Obesity and smoking both depress HDL levels. Low-fat diets result in lower levels of both HDLs and LDLs. Replacing saturated fat in the diet with polyunsaturated fat also will lower both of these lipoproteins. However, replacing saturated fat with monounsaturated fats, such as olive oil, seems to lower LDL cholesterol without having much effect on HDL cholesterol.


The level of HDLs in your blood is less important than the ratio of total cholesterol to HDLs. Your ratio of total cholesterol to HDL-cholesterol appears to be the best indicator of your risk of heart disease. Just divide your total cholesterol by your HDL. Ratios that are higher than 4.5 are often seen in people with heart disease. To significantly lower your risk, your ratio should be 3.5 or lower.


Scientists suggest that the reason that HDL levels drop on low-fat diets is that we don't need high levels of HDL to protect us from incoming cholesterol and saturated fat. So the drop in HDL cholesterol seems to be perfectly normal. Vegetarians tend to have very low levels of HDLs and also have low levels of heart disease. In countries where heart disease is rare, people tend to have very low levels of HDLs also.


A number of studies show that moderate consumption of alcohol raises HDL levels, although it isn't clear that this, in fact, has any real effect on heart disease risk. The disadvantages of alcohol consumption may outweigh any advantages. For women, this may be an especially inadvisable approach since even small amounts of alcohol may raise risk for breast cancer. Losing weight if you are overweight and giving up cigarettes if you smoke will also help to raise HDL cholesterol.


Two Harvard researchers suggest that the best approach to keeping LDL cholesterol low without lowering HDL cholesterol is to consume a more Mediterranean-style diet -- one that is very low in saturated fat and uses moderate amounts of the monounsaturated fat olive oil.