by Elizabeth Claire

Created on: January 22, 2009

How is the RDA of vitamin c determined?

The RDA, or Recommendation Daily Allowance, of Vitamin C, as well as for other vitamins and minerals, was originally developed during World War II using only sample populations, and were used merely as a point of reference regarding the nutrient levels needed in order to avoid chronic deficiencies in otherwise healthy adults.

Dr. Jeffrey Bland, founder of the Instutite of Functional Medicine, has stated publicly that, unfortunately, "the RDAs have absolutely no relevance to individual nutritional assessment. They are standards of identity to meet the needs of practically all healthy people to prevent the known nutrition disorders beriberi, pellagra, scurvy, kwashiorkor, rickets, and marasmus. They have nothing to do with the common disorders of Western society."

Last updated in 1989, RDA levels of all nutrients have not changed to take into account the rise in the popularity of processed foods, the growing stress levels of modern life, or the environmental factors of increased polution and decreases in the vitamin and mineral contents of modern food sources because of soil depletion. Additionally, because of the innate differences in each body, and depending on factors ranging from habits, such as smoking, to the genetic predisposition for specific diseases, the RDA is certainly not representative of the requirements needed on an individual basis to maintain health in the twenty-first century.

In recent years, doctors and nutritionists have observed and reported that because of evolutionary factors, supplementation in much higher doses than the RDA is now necessary for optimum nutrition. For example, in the case of Vitamin C, the RDA is 60 mg/day; please recall from above that this is the daily required intake of Vitamin C at which a healthy adult will not develop scurvy. Presently, many modern health care practitioners now recommend a minimum dosage of 2,000 mg/day in order to support optimum health. Proper levels of Vitamin C (ascorbic acid) in the body not only help to support the immune system, as a properly acidic environment works to inhibit bacterial growth, but also help, for example, to naturally lower blood pressure, counteract food allergies, and rid the body of any accumulations of heavy metals.

For a better measure of what your supplementation needs are, search for Optimal Daily Allowances (ODA). Depending on individual genetic and lifestyle factors, as well as personal habits, these recommendations more adequately support the modern needs of the human body.

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