| Are Dietary Supplements Necessary? The majority of people take one or more dietary supplements in the form of vitamins, minerals, herbs, botanicals, amino acids, or enzymes. The most common supplements include vitamin D, vitamin E, vitamin B12, calcium, iron, glucosamine, probiotics, fish oils, and herbs like echinacea and garlic. A growing number of packaged foods include supplements. As a result, you can get more of some supplements than you need. Often, more is not better and in some cases excessive amounts can be toxic. Ideally, we would get all nutrients from a healthy diet. Unfortunately modern life and the prevalence of processed foods make dietary supplements necessary in some situations. For example: • Calcium and vitamin D may be needed for keeping bones strong. • Folic acid decreases the risk of certain birth defects • Omega-3 fatty acids from fish oils can help some people with heart disease Scientific evidence supporting most other supplements is a work in progress. While many supplements have shown promise in limited trials more study is needed to determine their overall effect. Unfortunately, quality scientific studies of dietary supplements lack the patentable economic incentives that pharmaceuticals offer. As a result, few studies get funded. Recommendations for supplements often come with glowing endorsements from famous people, people with sketchy credentials and hearsay sources. Reading the fine print usually discloses that the recommendation is not based on scientific evidence. This does not mean the product will not provide some benefit although most often the benefit will be to the bottom line of the company selling the supplement. Dietary supplements sometimes contain ingredients that can have unexpected side effects. Here are a few examples: • Vitamin K can interfere with blood thinners • St. John’s wort can reduce the effectiveness of many drugs (antidepressants, birth control pills, etc.) • Antioxidant supplements, like vitamins C and E, can reduce the effectiveness of some cancer chemotherapies. • Too much vitamin A can cause headaches and liver damage, reduce bone strength, and cause birth defects. • Excess iron causes nausea and vomiting and may damage the liver and other organs. • In excessive amounts, comfrey and kava can harm the liver. While supplement companies are responsible for having evidence that their products are safe and label claims are truthful, they do not have to provide that evidence to the FDA before the product is marketed. Unfortunately, the art of creative advertizing often produces ads that skirt the law’s intent and proceed to cleverly suggest you have discovered a miracle cure. Reading to the end of these ads you will almost always find the required FDA statement, “This product is not intended to diagnose, treat, cure, or prevent any disease.” Hmm… a miracle cure that’s not guaranteed to do anything beyond separating you from your money. Do you need a supplement? Perhaps, however it would be difficult to know without a physical exam and perhaps certain supporting lab test. Fortunately, most of us get the nutrients needed from food and perhaps a multivitamin/mineral supplement. Excess from most supplements is excreted by the body. Before investing in expensive supplements keep in mind that the only beneficiary may be the supplement company. A Few Cautions • Be cautious about taking dietary supplements if you are pregnant or nursing. • Don’t give children more than a basic multivitamin/mineral product specified for children without fully understanding the potential side effects. • Don’t take dietary supplements to treat conditions that you have self diagnosed without consulting your doctor. • Don’t take supplements in place of, or in combination with, prescribed medications without your doctor’s advice. • Tell your doctor about the supplements you take if scheduled to have a surgical procedure. • The term “natural” doesn’t mean safe. Safety depends on how it works in your body, how it is prepared, and the dose. • Don’t be persuaded by slick ads or money back guarantees. These are marketing ploys intended to distract you from the absence of scientific evidence. • Always research the proven benefits, side effects, recommended dose, etc. While many dietary supplements are from natural sources they are seldom as good for us as the whole food they were extracted from. Often the process of extracting concentrated supplements destroys other nutrients. The danger is being oversold on the merits of supplements to the point of having a cupboard full of dietary supplements and little real food in the house. The produce isle is a better place to find nutrients than the supplement isle. Have a question about dietary supplements? The National Institute of Health provides up-to-date information on many dietary supplements. While I do recommend some dietary supplement, I usually recommend nature’s way (whole foods) first. As for nature’s way, why not join me for a morning walk. What better way to connect with the world around us. Nancy Neighbors, MD Huntsville, Alabama |