DISCLAIMER: THIS PAGE CONTAINS A GENERAL EDUCATIONAL DISCUSSION ON THE ABOVE TOPIC. IT IS NOT HEALTH ADVICE AND SHOULD NOT BE CONSTRUED AS SUCH. YOU SHOULD NEVER RELY UPON THE INFORMATION GIVEN HERE. YOUR PARTICULAR CIRCUMSTANCES MAY WELL REQUIRE AN ENTIRELY DIFFERENT APPROACH. YOU SHOULD NOT MAKE ANY CHANGES IN YOUR MEDICATIONS, DIET, ACTIVITY, LIFESTYLE, ETC. WITHOUT FIRST CONSULTING A LICENSED PHYSICIAN IN YOUR AREA.
There has been intense interest in the role of antioxidants in preventing disease for years accompanied by many unsubstantiated claims.
Many chemical reactions, in our bodies and elsewhere, consist of one substance being "oxidized" while another substance is "reduced." So naturally, you can find evidence of oxidation reactions almost wherever you look and the biochemical nature of disease is no exception. With regard to heart disease, oxidation of the bad (LDL) cholesterol molecule seems to be the initiating step that eventually leads to damage of the blood vessels.
In the past, some studies suggested that vitamin E in doses from 400 to 800 units a day may be beneficial for heart patients. However, the most recent and definitive studies have not demonstrated any benefit from Vitamin E (although patients with end-stage renal disease on hemodialysis may benefit from 800 units a day of Vitamin E). Similarly, there is no clear evidence of cardiovascular benefit from the other antioxidant vitamins, A and C.
Vitamin A is found in yellow-orange fruits such as cantaloupe, yellow-orange vegetables such as carrots, as well as green leafy vegetables.
Vitamin C is found in fruits, especially citrus fruits as well as red and green peppers, tomatoes. potatoes and green leafy vegetables.
Vitamin E is found in such dietary sources as soybeans, corn, safflower, cottonseed, whole grains, wheat germ, green leafy vegetables, canoloa oitl, olive oil, margarine, seeds and nuts (especially almonds and peanuts) as well as vitamin supplements sold in stores.
In some cases, antioxidant vitamins may actually be dangerous. Vitamin A supplemements actually increase the risk of cardiovascular disease as well as increasing the risk of lung cancer in cigarette smokers. High levels of vitamin A can cause other adverse effects such as dermatitis and severe, life threatening neurological problems. In pregnant women, excessive vitamin A levels can lead to fetal deformaties.
Excessive intake of vitamin C can lead to abdominal pain, nausea and diarrhea. It can promote the formation of kidney stones in patients with kidney disease.
Vitamin E is a blood thinner so cardiac patients already on other blood thinners could increase their risk of bleeding by taking vitamin E supplements. High vitamin E intake can cause nausea, flatulence and diarrhea. There is some evidence suggesting that high dose Vitamin E (400 IU daily and higher) may actually increase one's risk of death.
Thus, it may be better to eat the aforementioned foods that are rich in vitamins and other healthy nutrients rather than taking antioxidant vitamin supplements.
Selenium, zinc, manganese and copper are an antioxidant minerals but there is no definitive evidence to date that supplemention of these minerals has any health benefits.
Another class of antioxidant substances are the phytoestrogens. These are also sometimes referred to as polyphenols, isoflavones and flavenoids. They act as mild blood thinners and help dilate blood vessels. They are found in purple grapes and other fruits such as apples, cranberries, and strawberries; vegetables such as soy, legumes, onions and broccoli; green tea; cereal; red wine; purple grape juice; dark beer and chocolate, especially dark chocolate . These substances may explain why people who eat a lot of fruit and vegetables well as people who drink moderate amounts of alcohol have a lower risk of heart disease. Drinking tea seems to lower the risk of death in people with heart disease.
Probucol is an antioxidant medication but has the unfortunate side effect of lowering the level of good (HDL) cholesterol in our blood so it is not known if this medicine will be beneficial for long term use. Short term use in patients undergoing balloon angioplasty has been shown to lower the risk of the blockage reoccurring later on.
Since there is no firm scientific data that demonstrates beneficial effects for vitamins A, C, E or the flavenoids, there is no standing recommendation for people to take supplements of these substances. If you are interested in exploring these issues further, speak with your doctor. In the meantime, it is prudent to eat a well balanced diet that contains a lot of fruits and vegetables.
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