Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
About Dietary Supplements
Dietary supplements are vitamins, minerals, herbs, and many other products. They can come as pills, capsules, powders, drinks, and energy bars. Supplements do not have to go through the testing that drugs do.
Some supplements can play an important role in health. For example, calcium and vitamin D are important for keeping bones strong. Pregnant women can take the vitamin folic acid to prevent certain birth defects in their babies.
To take a supplement as safely as possible:
- Tell your health care provider about any dietary supplements you use
- Do not take a bigger dose than the label recommends
- Check with your health care provider about the supplements you take if you are going to have any type of surgery
- Read trustworthy information about the supplement
It sits within Food and Nutrition and Complementary and Alternative Therapies.
The lead U.S. institute for this subject is the NIH Office of Dietary Supplements.
When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.
Research on Dietary Supplements
2,672 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.
What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.
Research currently under way
- FAST for DM - Fatty Acid Supplementation Trial (FAST) for Dermatomyositis (DM)National Institute of Environmental Health Sciences (NIEHS)
- AIM-WEIGHT: AI-Guided Microbiome-Targeted Nutritional Intervention for Weight LossVarol TUNALI
- Dietary Supplements and Middle Aged Women (Creatine)Loughborough University
- Microbiome-Focused Food Supplement for Evaporative Dry Eye Due to Meibomian Gland DysfunctionVarol TUNALI
- Adherence Intervention in Patients With Metastatic Breast CancerColumbia University
- Supplementing Neuro-Energy to Aid CognitionUniversity of Pennsylvania
Research already completed
- Effects of Immulina TM Supplements With PASC PatientsUniversity of Mississippi Medical Center
- Spirulina Oral Supplement for Enhancing Host Resilience to Virus InfectionUniversity of Mississippi Medical Center
- Identification of Surrogate Blood and/or Urine Biomarker for Immulina TM (Trademark) in Normal HumansUniversity of Mississippi Medical Center
- Study Evaluating the Efficacy of Different Mixes of HMO-2FL + Humiome® Post LB on IBS Gastrointestinal Symptomsdsm-firmenich Switzerland AG
Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.
Where to read more
Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.
Start Here
- 5 Tips: What Consumers Need To Know about Dietary SupplementsNational Center for Complementary and Integrative Health
- Dietary and Herbal SupplementsNational Center for Complementary and Integrative Health
- Dietary Supplement Label Database (DSLD)National Institutes of Health, Office of Dietary Supplements
- Dietary Supplements: What You Need to KnowNational Institutes of Health, Office of Dietary Supplements
- FDA 101: Dietary SupplementsFood and Drug Administration
- MedlinePlus: Herbs and SupplementsNational Library of Medicine
- Multivitamin/Mineral SupplementsNational Institutes of Health, Office of Dietary Supplements
- Questions and Answers on Dietary SupplementsFood and Drug Administration
- Using Dietary Supplements WiselyNational Center for Complementary and Integrative Health
Related Issues
- Alerts and AdvisoriesNational Center for Complementary and Integrative Health
- Are Dietary Supplements Safe?American Cancer Society
- Dietary Supplements for Weight LossNational Institutes of Health, Office of Dietary Supplements
- Know the Science: How Medications and Supplements Can InteractNational Center for Complementary and Integrative Health
- Natural Doesn't Necessarily Mean Safer, or BetterNational Center for Complementary and Integrative Health
Clinical Trials
- ClinicalTrials.gov: Dietary SupplementsNational Institutes of Health
- ClinicalTrials.gov: Trace ElementsNational Institutes of Health
Medical subject headings
Clinicians and researchers index this subject under Dietary Supplements. These are the terms to use when searching medical literature.
This page is built from the MedlinePlus health topic record for Dietary Supplements, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.