You don't want to take supplements forever if you don't need them and you're not getting any benefit from them, because taking them in the long term can be quite successful. Dwyer says that vitamin D, calcium and folic acid are three nutrients you can overeat, especially through supplements. Many people choose to take supplements, but taking too much or for too long could be harmful. The Department of Health and Social Welfare recommends certain supplements for certain groups of people at risk of deficiency.
Some supplements can have side effects, especially if taken before surgery or with other medications. Supplements can also cause problems if you have certain health conditions. In addition, the effects of many supplements have not been tested in children, pregnant women, and other groups. So talk to your health care provider if you're thinking about taking dietary supplements.
If, while taking supplements, you also make changes to your diet to consume foods with a higher nutrient density, then it is fair to assume that your need to take supplements in the medium and long term will decrease. These include glucosamine (for joint pain) and herbal supplements, such as echinacea (for immune health) and flaxseed oil (for digestion). Because people find it difficult to get enough vitamin D from food alone, everyone (including pregnant and breastfeeding women) should consider taking a daily supplement containing 10 micrograms of vitamin D during the fall and winter. Folic acid supplements should be taken before you become pregnant, so start taking them before you stop using birth control or if there is a chance of getting pregnant.
Some population groups are at greater risk of not getting enough vitamin D and are recommended to take a supplement every day of the year. Because supplements are regulated as foods and not as drugs, the FDA does not evaluate the quality of supplements or their effects on the body. If you're pregnant, trying to have a baby, or could become pregnant, it's recommended that you take a 400 microgram folic acid supplement every day until you're 12 weeks pregnant. Johanna Dwyer, MD, RD, senior nutrition scientist in the Office of Dietary Supplements at the National Institutes of Health; professor of medicine (nutrition) and community health at the Tufts University School of Medicine.
It's not difficult to regularly ingest more than 1,000 micrograms of folic acid a day (the safe upper limit for adults) through fortified foods and supplements.
