The RDA, or Recommended Daily Dietary Allowance, is the amount of some vitamins and minerals established by the United States Food and Nutrition Board and National Research Council as the amount of nutrients to adequately meet the needs of practically all healthy people.Does the board definition mean that when your patient reports that he is taking the "supermarket special $1.99" multivitamin mineral supplement, or eating his bowl of fortified flakes each morning, that nutritional worries vanish? Many traditional allopathically-educated MDs or RDs will say yes. However, a different view is espoused by progressive health practitioners. Their view is to aim for the optimum, instead of the adequate. When the RDA states, "practically all healthy people," who do they include? I do not know the answer to that question, but I do know who they do not include. They do not include those who are sick with viral or bacterial infections (including the common cold). They do not include overweight people. They do not include heavy exercisers. They do not include smokers, drinkers, or heavy drug ingesters (including prescription medications). They do not include people under excessive stress from work/school relationships or finances. They do not include people who are wounded, the elderly, or those who have an acute or chronic traumatic injury. The next question might be, how many people do you know who do not fall into one of the previously-excluded categories? If your answer is similar to mine (not many), then the RDAs will be put in proper perspective. They certainly do not provide an optimal level and, for many people, not even an adequate level of nutrition.
How are the RDAs determined? No set standard or formula is applied. Some of the methods used include short-term human starvation studies, animal studies, and statistical analysis of standard population intakes correlated with the incidence of clinical nutrient-deficiency states. If a nutrient has no known deficiency state, evaluation of the average intake of the particular nutrient by the standard person is calculated. What does this mean? It means that the standard American who consumes the typical diet of low fiber, sugar enriched, highly processed, high-fat food is studied. As an example, since he shows no evidence of scurvy or beriberi, 60 mg of vitamin C or 1.5 mg of vitamin B1 is all that is necessary. The flaws in this scenario are obvious. With our chiropractic background, we see right away that healthy people are not being studied. As a student of nutrition and practicing nutrition, it is also quite apparent that there is a large gap between the amount of a nutrient needed to prevent a frank deficiency and the amount needed to block subclinical or subacute states. Referring to the vitamin C example above, slow wound healing, decreased immune response, easy bruising, and free radical damage are but a few of the many conditions that may occur in a person who only consumes 60 mg of vitamin C a day. In conclusion, do not be afraid to exceed the RDAs when supplementing your patients nutritionally. As chiropractors, our goal is one of optimal health for our patients and the general population. This goal mandates a clinical assessment of our patients' individual biochemical needs, needs the RDA may not, in all cases, supply.
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