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After menopause (heart attack is uncommon in women under fifty), the major risk factors for cardiovascular disease are thought to be similar to men: high blood pressure and elevated cholesterol and other fats in the blood in which both of which are influenced by diet and lifestyle.
Because cholesterol is one of the substances that cause plaque in artery walls, high cholesterol is a factor in cardiovascular disease. However, the relationship seems to be more complicated than we thought and is becoming controversial.
Cholesterol is found throughout our bodies and is needed for many functions; for example, it is a precursor for progesterone and all the sex hormones. As you may know, there are two main types of cholesterol which are carried in the blood stream, the bad cholesterol (Low-density lipoprotein/ LDL) and good cholesterol (High-density lipoprotein/ HDL) that transports cholesterol to the liver, where it is metabolized and then excreted; it is thought to be the good stuff--high levels of it seem to protect us from coronary mishap.
Triglycerides are another type of blood fat that raises the risk of cardiovascular disease; it appears that even when women have normal cholesterol, high triglycerides increase heart disease.
Generally, triglycerides should be between 50 and 150 mg per dl (decilitre), but in women anything over 100 may be too high. What is more important is what happens to cholesterol and your arteries when they become damaged from oxidation by free radicals.
Free radicals damage the vessels and oxidized cholesterol creates more free radicals, and your body lays down plaque over the damaged area as a protective mechanism. That's why there's been so much interest in antioxidant nutrients, such as vitamins C and E and beta carotene for cardiovascular protection. Other fatty and protein substances have been implicated in athero-sclerosis.
A blood fat called lipoprotein may be the first to adhere to the wall, and LDL then adheres to this sticky substance. Vitamin C seems the key in preventing this process. Elevated amounts of homocysteine, an amino acid, have recently been associated with clogged arteries and an increased risk of heart attack and stroke. Folate and vitamins B-6 and B-12 help get rid of excess homocysteine.
Platelets, the blood cells responsible for blot clotting, also play a role. When platelets form blood clots, they release inflammatory substances that damage the lining of the arteries; the clots also contribute to closing off the blood supply in arteries narrowed by atherosclerosis. This is why aspirin, which decreases the blood's tendency to clot, is recommended as a preventive.
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