Dear Dr. Blonz: My job keeps me on the road much of the time, and it is difficult to plan out my meals or to know what I will be eating. My husband is encouraging me to take a vitamin supplement, but I really don't like taking pills. Do you have some guidelines concerning supplements?--I.N., Austin, Texas
Dear I.N.: In recent years, vitamin and mineral supplements have moved beyond their fill-in-the-gaps image. The roots of this movement can be traced to concerns about the nutritional adequacy of the American diet. Measurements of food consumption have consistently shown that the average individual does not get the Recommended Dietary Allowance (RDA) of all the essential vitamins and minerals on any given day. Someone like you who travels a lot would be especially at risk.
The RDAs, however, were set up to stave off deficiency diseases. They're not rigid requirements that must be met every day, but goals to be met over time. This means there is little danger in missing an essential nutrient every now and then as long as your intake during a five- to 10-day period is at the RDA level. If there's a concern, it's for those who continually fail to eat properly. Although they may never develop a deficiency disease, a chronically deficient diet will likely have long-term health implications. So dietitians and other nutrition professionals focus on educating the public about the basic need for a healthy diet.
The plot, however, has thickened. There's mounting evidence that taking amounts far in excess of the RDA may offer measurable protection against common ailments and several age-related illnesses. In two long-term studies, for example, vitamin E was associated with a 40% decrease in the risk of heart disease. The minimum intake associated with this protection was 100 International Units of vitamin E per day--six to eight times the adult RDA. It's unrealistic to think that anyone could eat that amount in food alone, even with a diet that was a paragon of nutritional planning.
Besides vitamin E, there's growing evidence that the other anti-oxidants--such as vitamin C, the carotenoids and selenium--may provide extra benefits against heart disease, certain cancers, rheumatoid arthritis and cataracts. In addition, calcium, besides slowing the onset of osteoporosis, may be able to help prevent colon cancer and help lower blood pressure. Niacin has been used alone and in combination with other medications against elevated blood cholesterol; fiber can help in the fight against colon cancer; and omega-3 fats (fish oils), against heart disease.
One apparent problem with giving a nod to supplements is my concern that people could take the endorsement out of context. While a daily supplement can raise the intake of nutrients to recommended levels or beyond, an overdependence on pills could change the way we think about diet. It would be tragic if a person equated a "junk-food-plus-supplements" diet with one based on fresh whole foods. It doesn't even come close. Taking isolated nutrients in pills cannot equal consuming them in their natural state in food. Additionally, although there's significant knowledge about specific nutrients, science has only just begun to identify the variety of health-promoting compounds that are present in fresh whole foods.
Nonetheless, the case for supplements as a form of nutritional insurance has a lot going for it--not instead of a healthful diet, but in addition to it. A supplement cannot transform a poor diet into a healthful one, but it can help provide nutrients that the body needs.
If you decide to try a supplement, you should know what you're looking for; otherwise, you risk being cut adrift in a sea of inflated claims and misinformation. When selecting a multivitamin, look for pills that contain 100% to 300% of the RDAs. Pay special attention to the presence of vitamin E, C and selenium. Check the size of the pill and the suggested number you take every day. Opt for brands that include expiration dates.
Ed Blonz is the author of the "Your Personal Nutritionist" book series (Signet, 1996). Send questions to: "On Nutrition," Ed Blonz, c/o Newspaper Enterprise Assn., 200 Madison Ave., New York, NY 10016 or e-mail to: email@example.com. Personal replies cannot be provided.