Battle Is Still Raging Over Vitamin-Mineral Supplementation
Perhaps no other subject arouses as much acrimony among nutritional authorities as vitamin and mineral supplementation.
Firmly entrenched on one side are the skeptics who, like researchers at the U.S. Food and Drug Administration, call supplementation “a questionable and potentially harmful practice.” On the opposing side stand the apologists, who claim that taking megadoses of vitamins and minerals can extend the life span and boost the body’s immune system.
Between these two extremes are the many nutritionists and physicians who cautiously endorse taking a daily multiple supplement with 100% of the Recommended Daily Allowance (RDA) as “insurance” against nutritional deficiencies. The Food and Nutrition Board, the government agency that sets nutritional standards, defines the RDA as the amount of each nutrient necessary to keep most people in good health, based on available scientific knowledge.
“Supplementation may be warranted after age 50 because nutritional needs change and because the American fast-food diet makes it difficult to get complete nutrition,” said Maryanne Painter, a dietitian for Health Care Pharmacies in San Diego. “You may be a candidate if you don’t consume two servings of milk products daily, two servings of protein foods (such as lean red meat, fish and poultry), four serving of fruits and vegetables (one-half cup each) and four servings of starches, including cereals, breads and rolls.
Supplements should not provide more than 100% of the RDA, she warned, because certain vitamins, such as Vitamins A and D, become toxic in excessively high concentrations. High doses of Vitamin A, for example, may cause blurred vision and headaches, while excesses of Vitamin D may cause vomiting and diarrhea, weight loss and muscular weakness.
Wholesome Food
“Rather than megadosing on vitamins to make up for an inadequate diet, I recommend eating healthful, wholesome food and using vitamins as an adjunct to your diet,” Painter said. “If you listen to your body and eat a varied diet that incorporates your favorite foods in moderation, as Hippocrates said, ‘food will be your medicine.’ ”
Some nutritionists, however, claim that given our present agricultural and food-processing systems, relying strictly on unsupplemented diets can only create nutritional deficiencies.
Getting adequate nutrition from food “was possible 100 or even 50 years ago, when all foods were grown on fertile soils, were unrefined, and unprocessed, and contained all the nutrients nature intended them to contain,” writes Paavo Airola, a well-known nutritionist, in “The Holistic Health Lifebook.” “But today, when soils are depleted, when foods are loaded with residues of hundreds of toxic insecticides and other chemicals, the addition of vitamins and food supplements to the diet is of vital importance. “Nutritionally inferior and poisoned foods of today cause many nutritional deficiencies, derangement in body chemistry, and lowered resistance to disease.”
Some nutritional authorities do not fault the food system itself, but people’s lack of knowledge in balancing meals for adequate nutrition.
“Satisfying the RDAs at the dinner table is a wonderful goal but unrealistic,” said Paul Saltman, a University of California biology professor and author of “The California Nutrition Book.”
Safety Net
“Unless you’re a superb nutritionist and know how to balance foods to provide the essential micronutrients, you need supplements to act as a safety net to catch needs that fall through the dietary cracks.”
Unfortunately, government studies of older men and women reveal that more than half get less than two-thirds of the RDAs for calories and several vitamins and minerals, he said. Common deficiencies of the aging include shortages of calcium and Vitamin D necessary to combat osteoporosis, the trace minerals zinc and iron, and essential B vitamins, such as thiamine, Folacin, B-6 and B-12.
“Even if seniors consume 100% of the RDA, the figures established by the government may be inappropriate for them,” Saltman said. “There is only one set of RDAs for all men and women over 50, yet there is substantial evidence that people’s nutritional needs vary dramatically between 51 and 65 or 75.”
Nutrition-minded seniors intent on getting adequate amounts of key nutrients may encounter another problem: absorption. According to David Olson, a chiropractor in San Diego, many seniors have trouble absorbing calcium because they cannot produce sufficient stomach acid. Older adults also have trouble with Vitamin B-12 absorption, putting them at risk for pernicious anemia.
As the digestive system becomes less efficient in later life, supplementation may help offset problems caused by decreased absorption, he said. But people also can make life style changes to aid the digestive process.
Eat Calmly
“To increase absorption, it’s important for people to eat calmly,” he said, “otherwise digestion is hindered by anxiety. And people should chew their food throughly before swallowing, because an enzyme secreted in the mouth, ptyalin, begins to break down carbohydrates, facilitating digestion.”
Olson also recommends eating small, frequent meals throughout the day, easing the burden imposed on the digestive system. He also cautions taking fiber products--such as oat bran, apple pectin and wheat bran--apart from meals, because fiber blocks the absorption of certain key minerals.
Seniors who use over-the-counter and prescription medication need to be especially conscious of food-drug interactions, which may deplete bodily stores of important nutrients, said Jerry Hammond, a pharmacist and president of the San Diego County Pharmacists Assn.
Aspirin, for example, impairs assimilation of Vitamin C, he said. Mineral oils, found commonly in laxatives, decrease absorption of the fat-soluble vitamins, A, D, E and K. Diuretics deplete bodily stores of calcium, potassium, magnesium and zinc.
“If you take medication that interferes with vitamin intake, a multiple supplement may help replenish depleted nutrients,” Hammond said. “I recommend a supplement with 100% of the RDA, along with a calcium supplement to slow down the development of osteoporosis.”
Still, supplements cannot take the place of a well-balanced diet.
Advised Roslyn Alfin-Slater, professor of nutrition at UCLA’s School of Public Health: “Eat a low-fat, high-carbohydrate diet, get plenty of fruits, vegetables and whole grains, increase fiber consumption and drink eight glasses of fluid daily. Exercise the body and mind regularly, and in the process be sure to enjoy all the food that contributes to your health.”
