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Micronutrient expense and repletion of RDA levels

 

By William Misner, Ph.D.

William Misner, Ph.D.
William Misner, Ph.D.
From 1996 until his retirement in 2006, Dr. Bill worked full-time as Director of Research & Development at Hammer Nutrition. Among his many accomplishments, both academically and athletically, he is an AAMA Board Certified Alternative Medicine Practitioner and the author of "What Should I Eat? A Food-Endowed Prescription For Well Being".

RDA levels of micronutrient substrates are suggested to prevent deficiency disease disorders. RDA micronutrient substrates are depleted rapidly during energy expense or from an imbalanced dietary intake or from both, proportionate to energy demand and energy repletion rate. Energy is spent faster than it can be replenished. Energy efficiency expense has a dependant relationship from available micronutrient stores. Micronutrients provide the spark to fuel metabolism proportionate to their availability or replenishment following depletion. Muscle and liver glycogen stores are significantly depleted within 60-90 minutes during a moderate aerobic exercise event. Fluids losses also may result in a dangerous to health dehydration disorder within 3 hours in hyperthermic conditions. As energy is expended, micronutrients are proportionately depleted. When micronutrients are not replenished, human health is compromised. The endurance athlete is a model of depletion, repletion, and recovery mechanisms that may be stressed when more than RDA levels of macronutrients and micronutrients are not accessible for replenishment for recovery.

1. The body requires at least 40 nutrients that are classified into six groups: protein, carbohydrate, fat, vitamin, mineral, and water. These nutrients cannot be made in the body and so they must be supplied from solid or liquid foods
2. Fat, carbohydrate, and protein contain energy that is measured in units called kilocalories. Alcohol also contains kilocalories, but is not a recommended energy source for endurance exercise.
3.
Foods in endurance sports training programs should provide adequate fluids to prevent dehydration; energy intake that is high in carbohydrate, low in fat, adequate in protein, and that maintains desirable body weight and desirable proportions of fat and lean weight; and sufficient amounts of vitamins and minerals.
4.
Six categories of food types form the fundamentals of good diets for endurance exercise training and include: fruits, vegetables, grains-legumes, lean meats, low-fat milk products, and fats-sweets. Vegetarian diets include all food type categories except meat or milk products.
5. Fat and carbohydrate content of foods in each food type category varies greatly because of how foods are prepared.
6.
The food pyramid and sports food swap are guides for selecting foods that provide recommended amounts of essential nutrients for endurance exercise.
7.
Before, during, and after endurance exercise, food intake should include adequate amounts of easily digestible, high carbohydrate foods that are familiar and psychologically satisfying.
8.
Easily digestible high carbohydrate liquid or solid foods should be eaten soon after exercise is stopped to maximize rates of glycogen replacement.
9.
Dehydration can be prevented by adequate fluid intake before, during, and after exercise.
10.
Any food plan should be tested before a competition to find out how well that plan works for an athlete.
11.
A recent review of the protein needs of athletes indicates that requirements may be substantially above those of sedentary subjects, to account for the oxidation of amino acids during exercise as well as the retention of nitrogen during periods of muscle building. Current interest is focused on the mineral status of athletes, particularly that of iron and calcium. In the case of iron, there is a possibility that the increased level of loss by some endurance athletes will not be met by their usual dietary patterns.
12.
Diet sources of calcium may require attention, although iron requirements are reduced among postmenopausal women when compared with younger athletes.
13.
Athletes consuming less than 2000 calories a day may have difficulty meeting nutrient needs, particularly for iron and calcium. Weight loss, glycogen depletion, and dehydration also are possible results of an inadequate diet. Dietary strategies to enhance or maintain the body's carbohydrate stores are necessary for performance, especially for cyclists with high training miles or participating in road racing and other endurance events. Vegetarians and cyclists with low-calorie intakes may benefit from a multivitamin or mineral supplement.
14.
This is determined by caloric expense versus caloric intake, especially if dietary deficiencies occur in time-dependant, dose-depletion, or dose-deficiency fashion. Dietary analysis which I performed on 24 American endurance athletes over a 4 year period 1996-2000 concluded nutritional deficiencies from food intake alone in ALL 24 SUBJECTS...

MICRONUTRIENT DEFICIENCIES ARE A COMPONENT RISK OF DISEASE
Vitamins are a class of organic compounds that are components of an adequate diet. They or their derivatives function as coenzymes, cellular antioxidants, and/or regulators of gene expression. Fourteen vitamins are recognized in human nutrition (Vitamins A, B1, B2, B6, B12, C, D, E, K, niacin, folacin, pantothenic acid, biotin, choline), with deficiencies or excesses in intake leading to changes in protein, nucleic acid, carbohydrates, fat or mineral metabolism. Thus, the integrity of physiological systems, including those associated with detoxification, cellular repair, immune processes, and neural and endocrine function, depends upon the nutritional and vitamin status of the host. For these reasons, it may be anticipated that the adequacy of the vitamin supply to cells and tissues would affect the development, progress, and outcome of cancers. Although evidence based on studies in animal systems reveals that vitamin intake and status can modulate the outcome of experimental carcinogenesis, the findings are often conflicting and difficult to interpret. Furthermore, it is not yet possible to develop a suitable prediction of the role of the individual vitamins in tumor development. The significance of these observations for human nutrition and cancer prevention, particularly in reference to ascorbic acid (vitamin C), vitamin E, and B-complex vitamins is a suggested though not conclusive consideration.[5]

While none of the 5 reference authors conclude the requirement for vitamin or mineral supplementation above the RDA level, if the diet is balanced providing micronutrient levels high enough to prevent deficiency disorders, including cancer, a major killer in the USA. Mexico, bordering the USA reflects dietary disorders typical of many 3rd world nations. Researchers carried out a review of the studies related to vitamin deficiencies in the Mexican population published since 1950. Forty four studies were published from which it was concluded that:

  1. dietary intake data suggest that ascorbic acid, riboflavin and retinol intake are deficient: reported intakes were 40-70%, 35-64% and 20-72% of the recommended daily amounts respectively; niacin intake was also deficient in some studies.
  2. about 10% of Mexican children in rural areas had deficient values of plasma retinol (< 100 ng/ml) and about 25 to 30% had low values(100-200 ng/ml); this prevalence is reduced in children with a higher socioeconomic level.
  3. some studies were found that show the existence of marginal deficiencies of vitamin E, riboflavin and vitamin B12 in apparently healthy populations.

Further studies are required to identify the magnitude of these and perhaps other vitamin deficiencies and their potential effects on the health and function of the Mexican population.[6]

Worldwide micronutrient deficiencies exist proportionate to their lack in a imbalanced diet or in excessive energy expense, both of which tends toward depletion. While modern science has not concluded or agreed upon the resolution for supply and demand of micronutrient deficiency, they do suppose that micronutrient repletion may have a measurable impact in resolving or preventing some dietary deficiency disorders. Science tends to agree that whole food is the ideal source of micronutrient substrates. Supplemental forms of micronutrient substrates are concentrates of those found in food sources. Both forms are integral properties of the food chain, by which human survival is dose-dependant.

No organization should be permitted to inhibit access to non-toxic life-sustaining micronutrient substrates nor should any human be prohibited nutrient forms by which they may enhance quality of life, repletion of depleted micronutrients, or prevention of nutritional deficiency disorders.

REFERENCES

  1. Food selection for endurance sports, Houtkooper L Med Sci Sports Exerc 1992 Sep 24:9 Suppl S349-59.
  2. Sports nutrition. Approaching the nineties.Burke LM, Read RS, Sports Med 1989 Aug 8:2 80-100.
  3. Nutrition of the older athlete, Rock CL, Clin Sports Med 1991 Apr 10:2 445-57.
  4. Nutrition for cyclists, Grandjean AC, Ruud JS Clin Sports Med 1994 Jan 13:1 235-47.
  5. Vitamins and cancer prevention: issues and dilemmas, Young VR, Newberne PM, Cancer 1981 Mar 1 47:5 Suppl 1226-40.
  6. [Vitamin and mineral deficiency in Mexico. A critical review of the state of the art. II. Vitamin deficiency], Rosado JL, Bourges H, Saint-Martin B, Salud Publica Mex 1995 Sep-Oct 37:5 452-61.

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