A dietary supplement is any substance you take to improve your health or condition. This includes vitamins, minerals and herbs. The most common form is a pill, or capsule. You can also get them in powder, beverage, and food form. These supplements are not meant to cure diseases or health conditions. One exception is if the U.S. Food and Drug Administration (FDA) has approved it for a health claim.
The way to improve health
Vitamins and minerals are called micronutrients. They help nourish your body and keep you healthy. You can get them by eating a variety of foods in your daily diet. This ensures that your body can absorb them properly.
You should try to eat a variety of healthy foods, such as fruits, vegetables, lean meats, and fish. Otherwise, you may not be getting all the micronutrients your body needs. Taking a multivitamin may help. There is no evidence that they help reduce the risk of cancer or heart disease.
People who may benefit from a multivitamin include:
- Women who are pregnant or trying to get pregnant.
- Women who are breastfeeding.
- Women with heavy menstrual periods.
- Women who have gone through menopause.
- People who do not eat animal products. This includes vegetarians and vegans.
- People who have had gastric bypass surgery to lose weight.
- People with diseases of the stomach, liver, pancreas or gallbladder.
- People with digestive health conditions. This includes gastrointestinal disease, lactose intolerance or food allergies.
According to the United States Department of Agriculture (USDA), American adults may not be getting enough of the following micronutrients.
nutrition | Recommended Daily Intake (RDA) |
calcium | 1,000 milligrams (mg) for men and women ages 31-50 |
1,200 mg for women over 50 | |
1,000 mg for men 51-70 years old | |
1,200 mg for men over 70 years old | |
Fiber | 25 grams (g) for women |
38g for men | |
Folic Acid/Folate | 400 micrograms (mcg) |
Iron | 8 mg for men |
18 mg for women 19-50 years old | |
8 mg for women over 51 years old | |
magnesium | 320 mg for women over 50 |
420 mg for men over 50 | |
kali | 4,700 mg for men and women over 50 years old |
vitamin A | 2,310 international units (IU) for women |
3,000 IU for men | |
vitamin B12 | 2.4 mcg |
Vitamin C | 75 mg for women |
90 mg for men | |
Vitamin D | 600 IU |
800 IU for men and women over 70 years old | |
vitamin E | 15 mg |
Hundreds of other supplements are available. They promise to treat a wide range of symptoms. However, evidence to support these claims is often lacking. Some of the most popular herbs include:
- Chondroitin sulfate
- coenzyme Q10 (CoQ10)
- digestive enzymes
- bairnwort
- garlic
- Ginkgo
- ginseng
- glucosamine
- kava
- melatonin
- phytoestrogens, such as black cohosh, dong quai, and soy
- bioproducts
- dwarf palm tree
- John’s Wort
Talk to your doctor before you start taking a dietary supplement. He or she can tell you the benefits and risks of each supplement. Make sure he or she knows about anything you’ve done. This includes all drugs, both prescription and over-the-counter. That’s because some drugs and supplements can react badly. Read the ingredient lists on supplements to make sure you know what else is in there. Do not take more than the dose recommended on the label, unless approved by your doctor. Just because a supplement is advertised as “natural” doesn’t mean it’s safe.
Things to consider
Talk to your doctor if you don’t think you’re getting enough vitamins and minerals in your diet. He or she can help you decide which micronutrients you need. Your doctor may also recommend dietary supplements. This will depend on your overall health and lifestyle. Supplements can cause problems with cancer treatments or surgery. Your doctor will know if they interact with any health conditions you have.
For example, foods rich in vitamin E and beta-carotene are good for health. However, the United States Preventive Services Task Force (USPSTF) and the American Academy of Family Physicians (AAFP) recommend against taking vitamin E or beta-carotene for the prevention of cardiovascular disease and cancer. People who smoke or are at risk for lung cancer should also avoid beta-carotene. It may increase the risk of lung cancer.
Drug companies are subject to FDA regulations. Some supplement manufacturers follow the quality standards of the United States Pharmacopoeia Convention (USP). This means they volunteer to test their products. An outside company will check their quality and purity before selling them. These supplements display additional credentials on their labels. Look for them saying “USP Verified” or “ConsumerLab.com Approved Quality.”
Supplements are generally safe as long as they are not taken in excess. This is especially true for the fat-soluble vitamins A and E. Check the recommended daily intake (RDA) on the label. Taking too much can cause unwanted or harmful side effects.
However, some herbal supplements may not be safe. They may contain unlisted ingredients that make you sick. Medicines not listed on the label may include steroids or estrogens. The products may even contain harmful or toxic substances. Examples include arsenic, mercury, lead and pesticides. Supplements must be recalled if they are found to contain harmful ingredients.