When it comes to taking multivitamin supplements several questions arise. First, are they necessary for everyone? And if so, what are the appropriate amounts? And finally, are there significant differences in terms of purity and active ingredient delivery among products? Unfortunately the first two questions cannot be answered in a simple fashion. There is no compelling evidence that a healthy person with a diverse diet benefits from a supplement, and in fact a few disturbing studies have suggested that supplements could actually increase the risk of illness. But there is plenty of evidence for appropriate use during pregnancy or for medical conditions ranging from osteoporosis to anemia. But there are also some caveats. High intake of calcium, for example, has been linked with prostate cancer and vitamin K can interfere with the action of anticoagulant medication. Many people take supplements as sort of “nutritional insurance,” which is not unreasonable given that most probably do not have a balanced diet. Actually, there is no total scientific consensus on what constitutes a balanced diet. But many regulatory agencies around the world have made solid educated guesses about the amounts of vitamins and minerals in supplements that may deliver benefits without causing harm. Supplementing the diet with about 400 IU vitamin E, 1000 IU vitamin D and 500 mg calcium, for example, can be scientifically supported. The market is flooded with a plethora of products with such dosages, generally of similar quality.
ConsumerLab is an independent company that tests supplements and provides highly reliable information. After testing numerous products, a few were found to contain either more or less of some ingredients than listed on the label, but not by a significant amount. In rare instances the folic acid content exceeded the upper limit of safe levels, but not in any of the common products. Lead contamination was very rare, previous worry. Supplements disintegrated equally, meaning that there was no difference in the release of the active ingredients. With calcium, there is some indication that calcium citrate may be better absorbed than the commonly used calcium carbonate. The dietary supplement industry is very competitive and pricing is somewhat mysterious. The list of ingredients on the label of expensive products can look very similar to that of bargain basement supplements. Usually the manufacturers of the pricey items claim that they are more pure, and of higher quality. These tend to be multi-level marketing companies that also make unsupported health claims on behalf of their products. The ConsumerLab evaluation does not back up claims of higher quality. Generic and store brands fared as well as the expensive brand names, suggesting that for “nutritional insurance” the most economic products are an appropriate choice.
