As we become older, our arteries lose some of their elasticity and stiffen. This can lead to a progressive condition referred to as arteriosclerosis, the medical term for hardening (sclerosis) of the arteries. These stiffened blood vessels usually become clogged with fatty plaque, the hallmark of atherosclerosis (athero is the Greek term for porridge, which describes the thick, cheesy appearance of the deposits).
Some degree of atherosclerosis is a natural part of aging. It usually progresses slowly over years without producing noticeable symptoms. But serious problems develop when these stiffened blood vessels become severely narrowed with plaque. Complications include circulatory disorders, especially reduced blood flow to the lower legs and other extremities; angina, the chest pains caused by inadequate oxygen to the heart muscle; and heart disease and stroke.
By the time Western men have reached their late forties, most have some degree of atherosclerosis. In women the process is somewhat delayed, presumably due to the protective effects of estrogen during the reproductive years. After menopause, however, women quickly catch up with their male counterparts, and once in their sixties they are just as likely to develop severely clogged arteries as men are.
Precisely what initiates atherosclerosis is unknown. Most experts agree, however, that a genetic susceptibility and a combination of lifestyle factors accelerate the process; these include a diet high in fats and cholesterol, cigarette use, excessive stress, and lack of exercise. Poorly controlled diabetes and high blood pressure also contribute to atherosclerosis.
Arteries can be narrowed by 85 percent (or more) without producing symptoms. Nevertheless, there is still a high risk of a heart attack or stroke because clots tend to form at the site of fatty deposits. Most heart attacks are caused by a clot blocking a coronary artery (a coronary thrombosis); similarly, a cerebral thrombosis, or a clot that blocks blood flow to the brain, is the most common type of stroke.
EAT PLENTY OF
- Fresh fruits and vegetables for vitamin C, beta carotene, and folate.
- Wheat germ, nuts, seeds, and vegetable oils for vitamin E.
- Apples, oatmeal, lentils, and legumes for soluble fiber.
- Soy proteins in foods such as soy beverages, tofu, or tempeh.
- Salmon, sardines, and other cold-water fish for omega-3 fatty acids.
CUT DOWN ON
- Fats, especially saturated ones.
- Cookies, cakes, and snack foods rich in trans fatty acids.
- High-cholesterol foods.
- Smoking, obesity, high alcohol intake, and physical inactivity.
Researchers agree that diet plays a critical role in both the development and treatment of atherosclerosis. Cholesterol is the major component of atherosclerotic plaque, and numerous studies correlate high levels of blood cholesterol with atherosclerosis. Research indicates that atherosclerosis can be slowed and even reversed by lowering cholesterol in the blood—particularly the levels of low-density lipoproteins (LDLs), the bad type of cholesterol.
Elevated triglycerides, another type of lipid that circulates in the blood, also may contribute to atherosclerosis. People with diabetes tend to have high triglyceride and cholesterol levels, which may explain why diabetics are so vulnerable to heart disease.
Limit total fat intake
Dietary treatment for atherosclerosis entails limiting total fat intake to 20 to 30 percent of calories, with saturated fats (found mostly in animal products and palm, coconut, and palm kernel oils) comprising no more than 10 percent of calories. In addition to limiting saturated fats, experts suggest reducing intake of trans fatty acids and hydrogenated fats.
These trans fats are the result of hydrogenation and are known to raise your LDL cholesterol. Trans fats come in packaged foods such as cookies and crackers and snack food such as chips.
Although consumption of high-cholesterol foods is not as instrumental as a high-fat diet, a high intake of dietary cholesterol can raise the levels of blood lipids. Experts recommend limiting dietary cholesterol to 300 mg a day—about the amount in 11⁄2 egg yolks.
The omega-3 fatty acids in salmon, sardines, and other cold-water fish lower blood levels of triglycerides; they also reduce the tendency to form blood clots. Oat bran, oatmeal, lentils and legumes, pectin-containing fruits such as pears, apples, and citrus fruits, barley, guar gum and psyllium all contain soluble fiber that lowers blood cholesterol, probably by interfering with the intestinal absorption of bile acids, which forces the liver to use circulating cholesterol to make more bile.
Antioxidants may help
Studies indicate that beta carotene and vitamins C and E may protect against atherosclerosis by preventing LDL cholesterol from collecting in atherosclerotic plaque. Regular intake of soy protein may raise HDL cholesterol (the “good” cholesterol) as well as provide antioxidant protection.
Diet is not the only factor that contributes to atherosclerosis. Maintaining an ideal weight, abstaining from smoking, increasing exercise, developing effective methods of coping with stress, and keeping blood pressure and blood sugar levels within normal limits are also important.