Understanding Nutritional Supplements

Supplements fill pharmacy aisles and social media feeds, and it can be difficult to separate useful products from hype. A basic understanding of what supplements are, how they are regulated and what they can reasonably do puts you in a much stronger position as a buyer.

What is a dietary supplement?

Under U.S. law, a dietary supplement is a product taken by mouth that contains a “dietary ingredient” intended to add to the diet. Dietary ingredients include:

• vitamins and minerals;
• herbs and other botanicals;
• amino acids;
• other substances such as enzymes, probiotics and fish oils.

They come as tablets, capsules, softgels, gummies, powders, drinks and bars, and they must be labeled as dietary supplements.

Common categories

• Vitamins and minerals: single nutrients, such as vitamin D, or combinations, such as multivitamins.
• Specialty nutrients: such as omega-3 fatty acids. See our Omega-3 Fish Oil 1000 mg.
• Botanicals: such as echinacea, ginger and turmeric.
• Probiotics: live microorganisms.

How supplements are regulated

Supplements are regulated differently from medicines.

• The FDA does not approve dietary supplements for safety or effectiveness before they reach the market.
• Manufacturers and distributors are responsible for making sure products are safe and that label claims are truthful.
• Companies must follow good manufacturing practices designed to ensure identity, purity, strength and composition.
• The FDA can act against unsafe or mislabeled products after they are on sale.

This means that the presence of a product on a shelf is not evidence that it has been tested for effectiveness.

What supplements can and cannot do

Some supplements have well-established roles. Calcium and vitamin D support bone health, folic acid reduces the risk of certain birth defects, and vitamin B12 prevents deficiency in people who do not get enough from food. For many other products, the evidence is limited or mixed.

Supplements are not permitted to claim that they treat, diagnose, cure or prevent diseases. Be wary of any product that does.

Who might benefit

• People who are pregnant or might become pregnant
• Older adults
• People following vegan or other restricted diets
• People with medical conditions that affect absorption
• People with a diagnosed deficiency

A healthcare professional can help identify whether you fall into one of these groups.

Risks to be aware of

• Interactions: some supplements change how medicines work.
• Excess: more of a nutrient is not better, and some are harmful in high doses.
• Surgery: some supplements affect bleeding or anesthesia.
• Replacing treatment: using supplements instead of prescribed medicine can be dangerous.
• “Natural” does not mean safe.

Spotting doubtful products

The FDA warns consumers to be cautious about products that promise quick fixes, claim to cure a wide range of unrelated diseases, use phrases such as “miracle cure” or rely on personal testimonials instead of evidence.

Using supplements sensibly

1. Decide what the supplement is for.
2. Check reliable sources, such as the NIH Office of Dietary Supplements fact sheets.
3. Read the label and follow the directions.
4. Tell your doctor and pharmacist what you take.
5. Report any bad reaction to your doctor and to the FDA.

The bottom line

Supplements are tools for filling specific nutritional gaps, not substitutes for food or medical care. Choose them for a clear reason, read the label and involve a professional. Browse by nutrient in our vitamins and nutrition range.

Sources

1. NIH Office of Dietary Supplements. Dietary Supplements: What You Need to Know.
2. U.S. Food and Drug Administration. Dietary Supplements.
3. U.S. Food and Drug Administration. Questions and Answers on Dietary Supplements.
4. National Center for Complementary and Integrative Health. Using Dietary Supplements Wisely.