Vitamin C fights on many fronts in the battle for health.We have long known that a diet rich in vitamin C from fruits and vegetables provides protection against cancer and heart disease. Historically, however, little evidence has been available concerning the benefits of supplementation with vitamin C. More studies are being done and the evidence is beginning to mount. Research by the National Institute on Aging has shown that elderly people who consistently supplement with vitamins C and E have a 50% lower risk of dying prematurely. Another study in California bumps the reduction rate to 60% for people who consume at least 750 mg per day of C. Vitamin C is a water-soluble vitamin that humans, unlike other mammals, cannot manufacture. For us, then, it must be consumed through the diet. It is necessary for the synthesis of collagen, a structural component of bones, ligaments, tendons and blood vessels. It is important for the synthesis of norepinephrine, a neurotransmitter involved in normal brain function and in affecting moods. It has been shown to help metabolize cholesterol and transport fat for conversion to energy. It is perhaps the best known of the antioxidants, working to protect DNA and RNA as well as proteins, fats and carbohydrates from the damaging effects of free radicals. It is also believed to regenerate other antioxidants in the body. The recommended daily allowance (RDA) was recently reestablished from the previous 60 mg per day. The recommendation is somewhat higher for smokers because smoking increasing oxidation. Still the RDA is based on the amount that is required to prevent deficiency diseases like scurvy rather than for the prevention of chronic diseases such as cancer and heart disease. The First National Health and Nutrition Examination Study (NHANES I) found that death from cardiovascular diseases was 42% lower in men and 25% lower in women who had a total vitamin C intake (combined diet and supplementing) of about 300 mg per day. The Nurses' Health Study involved more than 85,000 adult women who had intakes exceeding 359 mg per day. The results showed a 27 – 28% decrease in heart disease risk. The plasma saturation level of C has been established at 400 mg by the National Institute Of Health. Many wholistic practitioners suggest maintaining the saturation level by ingesting in excess of 10,000 mg of C per day in order to fight chronic conditions like cancer and heart disease. Because Vitamin C is water-soluble and dissipates quickly in the body it must be ingested more than once per day. Many case studies have shown that high intakes of vitamin C are linked to decreased incidence of cancers of the stomach, rectum, lung, mouth, throat and esophagus. In prospective studies it is generally found that those who consume at least 80 to 110 mg per day have a significantly reduced cancer risk. Though these levels are not near the saturation level of 400 mg per day cancer risk is still decreased significantly. In the Nurses' Health Study it was found that premenopausal women with a family history of breast cancer had a 63% lower risk of breast cancer if they consumed an average of 205 mg per day of vitamin C compared to those who consumed an average of 70 mg per day. The Swedish Mammography Cohort found that overweight women consuming about 110 mg per day had a 39% reduced risk of breast cancer than overweight women consuming less than 32 mg per day. Vitamin C, along with other antioxidants like vitamin E, beta-carotene and selenium fight cancer by neutralizing the free radicals and toxins before they can initiate the gene mutation that leads to cancer. People with low antioxidant intake, therefore, have a higher risk of developing cancer. A strong immune system is essential to fighting cancer. In addition to a healthy diet it is imperative to supplement with vitamins and minerals, especially antioxidants. Lead toxicity is another health risk that can be reduced by sufficient intakes of vitamin C. Abnormal growth and development have occurred in infants of women exposed to lead during pregnancy. Children chronically exposed to lead often show an increased likelihood of learning disabilities and behavioral problems. High lead exposure can also cause high blood pressure and kidney failure. In a study involving older men it was found that blood lead levels were significantly higher in those ingesting an average of less than 110 mg per day of vitamin C compared to men ingesting higher levels. A larger study confirmed these results showing higher blood levels of vitamin C were associated with lower levels of lead. Seventy-five male smokers were found to reduce their blood lead levels over a four-week period by ingesting 1,000 mg per day.
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