Free consumer checklist

How to Check Supplement Information Before You Trust It

Supplement claims can sound certain even when the evidence is not. Check who is making the claim, what researchers studied, and whether key safety facts are missing.

Start the five-minute checklist

Last reviewed July 21, 2026

Step 1

Start with the exact claim

Write the claim in plain language. Is the product supposed to help you get enough of a nutrient, support a body function, reduce a risk, or treat a disease?

This difference matters. The U.S. Food and Drug Administration does not approve dietary supplements for safety and effectiveness before they are sold. A label may say that an ingredient supports a normal body function. This is called a structure/function claim, and the FDA does not approve each such claim before it appears on a label.

Be cautious when a supplement is advertised as “FDA approved” or promises to diagnose, treat, cure, or prevent a disease.

Official background: FDA approval explained and NIH supplement guidance.

Step 2

Check who wrote the information

A trustworthy page should make several basic facts easy to find:

Who runs the website?
Is the page educating you, selling a product, or both?
Does it name its sources?
Was it reviewed by someone trained in health or medicine?
Does it show when the information was updated?
Does it explain how errors are corrected?

Look beyond the web address. Government, university, hospital, and nonprofit sites can be useful places to start, but check each page. On a commercial site, separate product marketing from independent information.

See NCCIH's tutorial on finding reliable health information online.

Step 3

Ask what the research actually tested

“A study found” is only the beginning. Ask whether the result fits the claim you are trying to check.

Subjects: Was the supplement tested in people, animals, or laboratory cells?
Participants: How many people took part, and were they similar to you?
Comparison: Did the study use a placebo, another treatment, or no comparison?
Product: Did it test the same ingredient form and dose?
Time: Was it long enough to find benefits and side effects?
Outcome: Did it measure something people feel or experience, or only a laboratory marker?
Replication: Have other studies found a similar result?

A randomized controlled trial, often shortened to RCT, puts people into groups by chance. One group gets the supplement. Another gets a comparison, such as a placebo. This can reduce some types of bias, but one RCT does not settle a question. A small or short study may not tell us what happens for everyone.

NCCIH offers a printable checklist for understanding health news stories.

Step 4

Check safety separately from benefit

A supplement may help with one outcome and still be unsafe for some people.

Supplements can interact with medicines, affect lab tests, or be a poor choice during pregnancy, breastfeeding, illness, or before surgery. Keep an up-to-date list of every supplement and medicine you use. Share it with your doctor or pharmacist, especially when you start a new product or your prescriptions change.

Start with NIH ODS fact sheets, MedlinePlus herbs and supplements, or FDA safety updates.

Step 5

Read the label without overreading it

The Supplement Facts label lists active ingredients, amounts per serving, and the suggested serving size. Check the exact ingredient form and the amount in the full daily serving. A product name on the front may not tell you either one.

Daily Value (%DV): Shows how much a serving adds to a general daily reference amount. It does not show how effective the product is for a health goal.
Standardized: Does not, by itself, guarantee product quality.
Proprietary blend: May list only a combined total rather than the amount of each ingredient.
Quality seal: May help confirm ingredients, manufacturing, or contaminant testing. It does not prove a supplement is safe or effective for you.

A missing warning on the label does not prove that a supplement has no side effects.

The Dietary Supplement Label Database shows what manufacturers report on labels. It does not establish that a product works.

Printable tool

A five-minute checklist

Check each box you can before relying on a supplement claim.

I can state the exact claim in one sentence.
I know who wrote the information and whether they sell the product.
The page names its sources and shows when it was updated.
The evidence includes research in people, not only animals or laboratory cells.
I checked whether the ingredient form, dose, participants, and study length match the claim.
I looked for limits, side effects, and medicine interactions.
I read the full Supplement Facts label and serving size.
I compared the claim with information from NIH, FDA, NCCIH, or MedlinePlus.
My doctor or pharmacist knows about the supplements and medicines I use.

An empty box does not prove that a product is unsafe or does not work. It shows where you need more information before making a decision.

Keep checking

Trusted starting points

These public resources are useful places to verify labels, safety information, and how a health claim is supported.

Source	Best used for
MedlinePlus Dietary Supplements	Plain-language overviews and links to federal health resources
NIH Office of Dietary Supplements	Ingredient fact sheets, safety, interactions, and consumer guidance
NCCIH Know the Science	Understanding studies and evaluating health information
FDA Dietary Supplements	Regulation, warnings, recalls, and reporting safety problems
Dietary Supplement Label Database	Information copied from supplement labels sold in the United States

About this guide

Healthy Aging Atlas prepared this page as a general health-information resource. It does not recommend a product, rank brands, or provide individual medical advice. This page contains no affiliate links.

Found an error? Email info@healthyagingatlas.com.