Do you need to take dietary supplements?
Looking at vitamins, minerals, botanicals and more
When you get that bottle of vitamin C or fish oil pills, you might wonder how well they work and whether they’re safe. The first thing you have to ask yourself is whether you need them first.
Every day or occasionally, more than half of all Americans take one or more supplements. Add-ons are available without a prescription and usually in a pill, powder or liquid form. Botanical products, vitamins, minerals and herbal products are common supplements.
People use these supplements to ensure they get enough essential nutrients and maintain or improve their health. But not everyone has to take supplements.
“All the nutrients you need can be obtained by eating a variety of healthy foods, so you don’t have to eat any,” says Carol Haggans, a registered dietitian and consultant at NIH. “But supplements may help you fill your dietary gaps.” Some supplements may have side effects, especially if taken before surgery or with other medications. Additions can also cause problems if you have certain health conditions. And the effects of many supplements on children, pregnant women and other groups have not been tested. If you plan to take dietary supplements, talk to your health care provider.
“Together with your doctor, you should discuss the supplements you are taking to integrate and manage your treatment,” says Dr. Craig Hopp, a NIH botanical research expert.
Dietary supplements are regulated in the U.S. Food and Drug Administration (FDA) is food, not drugs. Some health benefits can be claimed on the label. Unlike drugs, however, supplements can not claim to cure, treat or prevent a disease.
“There is little evidence that any supplement can reverse any chronic disease,” Hopp explains. “Do not use this expectation as supplements.” Evidence suggests that some supplements may improve health in different ways. The most popular nutrient supplements are multivitamins, calcium, and B, C, and D. Calcium supports the health of the bone and helps the body absorb calcium with vitamin D. Vitamins C and E are antioxidants — molecules that prevent cell damage and help maintain health.
Women need iron during pregnancy, and infants need vitamin D. Folic acid—400 micrograms daily for all women of childbearing age, whether from supplements or fortified foods.
Vitamin B12 maintains nerve and blood cell health. Vitamin B12,’ says Haggans,’ comes mainly from meat, fish and milk products, so vegans can take a supplement to make sure they get enough of it.
Research suggests that fish oil can support heart health. Of the supplements not derived from vitamins and minerals, Hopp said, “Fish oil probably has the highest scientific evidence to support its use.” Glucosamine and herbal supplements such as echinacea (immune health) and flaxseed oil (digestion). These are also included.
Many additives have mild effects with low risk. But be careful. For example, vitamin K will reduce the ability of blood thinners to work. Ginkgo can thin your blood. The St. John’s word herb is sometimes used to relieve depression, anxiety, and nerve pain, but it can also accelerate the breakdowns of many medications, such as antidepressants and birth management pills.
Just because a supplement is promoted as “natural,” it doesn’t need to be safe. The herbs comfrey and kava, for example, can seriously harm the liver.
“The chemical makeup is important to know how it is prepared and how it works in the body— especially for herbs, but also for nutrients,” says Haggans. Haggans. ‘ Talk to a health care provider to advise on whether you need a first supplement, the dose and possible interactions with medicinal products you are already taking.’ See Daily Value(DV) percent for each vitamin and mineral nutrient to ensure that you do not get too much. “It’s important to consider the DV and the upper limit,” says Haggans. Too many of the supplements can be harmful.
Scientists still have much to know about common vitamins. In a recent study, unexpected evidence of vitamin E has been found. Previous research suggested that men who have taken supplements with vitamin E may have a lower risk of prostate cancer. “But to our surprise, in a major NIH-funded clinical trial, more than 29,000 men found that taking vitamin E supplements actually increased–not decreased–their risk,” explains Dr Paul M. Coates, NIH’s Diät Supplements Director. That’s why supplemental clinical trials are important to confirm their effects.
Since supplements are regulated as foods rather than as drugs, the FDA does not assess the quality or impact of supplements on the body. If a product is found unsafe after it reaches the market, the FDA may limit or prohibit its use.
Manufacturers also have responsibility for the product’s purity and must accurately list the ingredients and their quantities. However, there is no regulatory agency that ensures that labels match the bottles. You may lose or sometimes get more from the listed ingredients. It is not possible to list all the ingredients.
A number of independent organizations conduct additional quality tests and provide approval seals. This does not guarantee the product to function or is safe, it only guarantees that the product has been properly produced and contains the listed ingredients.
“Products sold nationally and online in shops that are usually okay,” Coates says. “According to the FDA, pharmaceutical supplement products most likely to be infected are herbal remedies promoted for weight loss and improved athletic or sexual performance.” To make it easier to find information reliably, NIH has fact sheets on ods.od.nih.gov/factsheets and list-all / factsheets for dietary supplements. NIH has recently launched an online label database on dietary supplements at www.dsld.nlm.nih.gov. This free database allows you to search for ingredients for thousands of dietary supplements. It contains data from the label on dosage, health claims and precautions.
Check the free updated NIH application for your smartphone or tablet: My Dietary Supplements (MyDS) for more personalized information about dietary supplements on the go.
The MyDS app provides the latest additional information and allows you to track the vitamins, minerals, herbs and other products you are taking. You can even check supplements for your parents, spouse or children.
“Deciding whether to use supplements or not and which supplements is a serious matter,” Coates says. “First learn about your potential benefits and risks. Talk to your health care providers about products of interest and decide together what, if any, is best for your overall health.