Vitamin A - Fights Heart Disease
March 21st, 2008Many studies have shown that people with high levels of beta carotene in their diet not only have a less likely chance of developing cancer, especially of the lung, but also of the rest of the GI tract such as the throat, esophagus, and mouth. It takes at least 12 years of high doses of beta-carotene to thwart the onset of cancer of the lung. A Harvard Study of male physicians taking 50 mg supplements of beta carotene every other day for 6 years showed that the control group had only half the number of fatal heart attacks and strokes compared to the general population. Another Harvard study of 90,000 female nurses show that those eating the most beta carotene (more that 11,000 I.U. per day) had a 22% lower risk of heart disease than those getting less than 3,800 I.U. per day. In addition, the study showed that those women who ate at least 5 carrots a week were 68% less likely to have strokes compared to the normal group. Eating a high volume of spinach also cut the stroke risk by 40% (spinach contains a lot of beta-carotene!!).
The Alliance of Aging Research suggests that adults should take 10 mg (17,000 I.U.) to 30 mg (50,000 I.U.) per day of beta-carotene for life. One cup of carrot juice equals 24.2 mg and one medium sweet potato equals 10 mg. Incidentally, heavy cooking destroys beta-carotene.
If you want extra insurance against aging, many researchers favor a supplement of 15,000 to 25,000 I.U. of beta-carotene per day. Beta-carotene should be taken with meals because it dissolves in the fat easily, which increases its absorption. Beta-carotene derived from a plant source is safe and non-toxic at up to 100,000 I.U. per day.
Plain-type vitamin A is derived from animal foods such as liver and can build up to toxic levels in your liver and is found in most supplements in the form of retinal Vitamin A. Adults should take no more than 5,000 to 10,000 I.U. of this type of Vitamin A. High doses (more than 25,000 I.U. daily) of Vitamin A itself can cause hypervitaminosis, a condition characterized by yellowing of skin, blurred vision, loss of appetite, diarrhea, and muscular weakness, that disappears when the intake is cut back.
As far as anti-oxidants are concerned, both beta-carotene and Vitamin A are effective on their own. Together, their collective effect is greater than one alone. In a Harvard study of female nurses, it is shown that there was a 34% drop in heart disease in those taking vitamin E alone; 22% drop in cardiovascular disease in those taking beta carotene alone; and 20 % drop in heart disease in those taking vitamin C alone. For those taking the highest amount of all three anti-oxidants, the rate of heart disease dropped 50%.
