Cedars-Sinai Blog

Q&A: Vitamins and Supplements

Colorful vitamins and supplements.

Fit teas, magic powders, special pills—there's so much advertising that promises that you'll be healthier if you just add these to your diet. But are they actually healthy or are they a scam?

Unlike the prescription medications that you take, dietary supplements are not put through strict safety and effectiveness requirements, so it can be hard to know what's real.

We chatted with Stephanie Wages, registered dietitian, to learn more about how vitamins and supplements should fit into your healthy routine.

"Some supplements are useful in reducing the risk of certain diseases and are authorized to make label claims."

Q: What is a supplement?

Wages: A dietary supplement is a product taken by mouth that contains a "dietary ingredient."

Dietary ingredients include vitamins, minerals, amino acids, and herbs or botanicals—as well as other components that can be used to supplement the diet. Dietary supplements can be used to help if you are lacking a nutrient in your diet or have been diagnosed with a deficiency.

Dietary supplements are not meant to treat, diagnose, or cure diseases. However, some supplements are useful in reducing the risk of certain diseases and are authorized to make label claims. For example, folic acid supplements may make a claim about reducing the risk of birth defects of the brain and spinal cord.

Q: How are vitamins and supplements different?

Wages: Dietary supplements can come in many forms, including tablets, capsules, powders, energy bars, and liquids. Vitamins are a type of supplement. Multivitamins are the most common dietary supplement used in the US.

Q: How do I know if I need to be taking a dietary supplement?

Wages: If you suspect that you're deficient in a nutrient, make an appointment with your doctor or dietitian and tell them about your symptoms. They can run blood tests to determine if there is a deficiency, and they can recommend safe ways to supplement your diet.

Q: What should I discuss with my doctor before taking supplements?

Wages: It is important to make sure you check with your doctor or other healthcare professional before taking supplements because there are certain health conditions where taking supplements may put you at risk. And you should tell your doctor prior to surgery if you are taking supplements.

Q: How can I tell that my supplements are safe?

Wages: Do not assume the term "natural" guarantees that the product is wholesome and safe. Contact the manufacturer for information about the product before you use it.

Be aware that some supplement ingredients—including nutrients and plant components—may be toxic. Some ingredients and products can be harmful when consumed in high amounts, when taken for a long time, or when used in combination with certain drugs, substances, or food.

Your doctor can help determine whether the product is safe for you to take. They can also help sort through reliable information from questionable information.

Q: What should I do if I have new side effects from a supplement?

Wages: If you experience an adverse effect, contact your doctor or healthcare professional immediately. Both you and your doctor are encouraged to report the problem to the Food and Drug Administration as soon as possible.

Q: Are there specific things I should look out for based on age/gender?

Wages: There are supplements with doses and amounts of ingredients specific to certain age groups or genders.

For example, pediatric vitamins are made with specific doses that are safe for children. It is not safe for children to consume supplements intended for adults.

It is important to read the label completely before taking a supplement to make sure it is appropriate for you.

There are also specific populations where micronutrient supplementation is recommended. Examples for different populations include iron and vitamin D supplementation for exclusively breastfed infants, folic acid for women who become pregnant, and vitamin B-12 for people older than age 50.