Dietary supplement vs drug: how FDA regulation differs

The biggest difference is timing. A new drug must be shown to be safe and effective for its intended use before it can be sold in the United States. A dietary supplement does not go through that process: under the Dietary Supplement Health and Education Act of 1994 (DSHEA), the FDA cannot approve a supplement for safety or effectiveness before it is sold, and the agency's role mostly begins after the product is on the market.

That gap explains many things you see on sales pages, from disclaimers to missing dose information. This guide compares the two systems side by side, using FDA pages we opened while writing. It is general information, not medical advice, and it is not a substitute for asking your doctor or pharmacist about anything you take.

How does a drug get approved?

The FDA's drug pages describe a long, staged process. The company first does laboratory and animal testing, then must show the FDA the results and its plan for human testing before studies in people can begin. Human studies run in phases. Phase 1 usually involves 20 to 80 people and looks at side effects. Phase 2 has a few dozen to about 300 people and looks for early signs of effectiveness. Phase 3 usually involves several hundred to about 3,000 people and gathers more information about safety and effectiveness.

Then the company files a New Drug Application with all animal and human data and details of how the drug is made. FDA doctors, statisticians, chemists and other scientists review the data and the proposed labeling. The FDA says approval means the data were reviewed and the drug was determined to provide benefits that outweigh its known and potential risks for the intended population. It also says the agency generally expects two well-designed clinical trials, though one convincing trial may be enough in some cases, such as rare diseases.

An approved drug carries an FDA-approved label that describes its benefits and risks. Sometimes the FDA requires further studies after approval as well.

How do dietary supplements reach the market?

Congress defined the term "dietary supplement" in DSHEA. A supplement is a product intended for ingestion that contains a "dietary ingredient," such as a vitamin, mineral, herb or other botanical, amino acid, or a concentrate, metabolite, constituent or extract of these. It must be swallowed, so topical or inhaled products are not supplements, and the label must call it a supplement or use an equivalent term.

The FDA's consumer Q&A says that under DSHEA the agency does not have the authority to approve dietary supplements before they are marketed. Generally, a firm does not have to give the FDA the evidence it relies on for safety, before or after it markets its products. The manufacturers and distributors have initial responsibility for making sure their products meet the safety standards, and the FDA can act when an unsafe product reaches the market. The FDA also says that unlike drugs, which must be proven safe and effective for their intended use before marketing, there are no provisions in the law for it to approve supplements for safety before they reach consumers.

Because of this, the FDA says it often does not know when new products come on the market, and it cannot keep a complete list of all supplements sold in the country.

What is the one premarket exception for supplements?

New dietary ingredients. A "new dietary ingredient" is one that was not marketed in the United States before October 15, 1994. If a supplement contains one, and it is not already in the food supply in a form that has not been chemically altered, the company must notify the FDA at least 75 days before selling it. The notification must include the safety information the company relies on to conclude the ingredient will reasonably be expected to be safe under the conditions in the labeling.

That is a notice, not an approval. The FDA reviews these notifications, but the pages we read do not describe it as a finding that a product works.

Side-by-side: how the two systems differ

Question	Drug	Dietary supplement
Proof of safety and effectiveness before sale	Required and reviewed by the FDA	Not required to be submitted to the FDA
FDA approval of the product	Yes, through an application	No. The FDA has no authority to approve supplements before sale
Who is responsible for safety at first	The company, checked by FDA review	The manufacturer or distributor
Disease claims	Allowed if reviewed and approved	Not allowed. A product marketed for a specific disease is regulated as a drug
Manufacturing rules	FDA quality requirements	Current good manufacturing practices for supplements
Label content	FDA-approved labeling	Supplement Facts panel, not pre-approved

The two systems also differ in how claims are handled. The FDA's label claims page says health claims, which link a substance to reduced risk of a disease, need FDA review and authorization or a notification process, while structure/function claims and dietary guidance statements are not subject to premarket review and authorization by the FDA. That is why "supports" language is so common on supplement pages.

What rules do supplements still have to follow?

Quite a few. The FDA requires manufacturers, packers and holders of supplements to follow current good manufacturing practices meant to help ensure the identity, purity, quality, strength and composition of supplements. Facilities that make, process, pack or hold supplements for US consumption must register with the FDA. The FDA periodically inspects manufacturing facilities, reviews labels and websites, examines imports and investigates complaints.

Labels must carry the product name and a "dietary supplement" statement, the name and place of business of the manufacturer, packer or distributor, a Supplement Facts panel, a list of other ingredients, and the net quantity. The Supplement Facts panel must list the serving size and servings per container, declare each dietary ingredient, and, except for ingredients in a proprietary blend, give the amount per serving. Our GlucoTrust review notes that the sales page prints no amount for any ingredient, and our Java Burn review flags the same gap for its ingredient list, which is why we check the actual label before we score a page.

One surprise for many readers: the FDA says there are no laws or regulations that limit the serving size of a supplement or the amount of a dietary ingredient in one serving, other than the manufacturer's responsibility to meet the safety and labeling rules. A high number on a label is not evidence of anything.

How does adverse-event reporting work for each?

Supplement companies must record, investigate and forward serious adverse event reports to the FDA. The FDA's consumer page says firms must report serious events they receive within 15 days, and labels must carry a domestic address or phone number for such reports. Consumers and doctors can report too, through the Safety Reporting Portal. The FDA says it evaluates these reports to identify early signals that a product may present safety risks.

For drugs, safety monitoring continues after approval, and the FDA's MedWatch program takes voluntary reports about medical products, including drugs, from patients and health professionals. Industry reports are mandatory in a separate electronic format. Supplements are covered by MedWatch too, but the FDA's supplement page points reports to the portal. Our review method treats a missing seller address or unclear contact details as a transparency problem for that reason.

What does this mean when you read a sales page?

It means the words on the page carry different weight. "FDA approved" is a drug term. A supplement page that says it is approved is either loose or wrong, as we explain in our reviews when we see it. A page that promises to treat a specific disease is describing a drug, and the FDA says such a product is regulated as one.

Use this short checklist:

1. Look for "supports" language and the FDA disclaimer. Together they mean the claim was not reviewed by the FDA.
2. Read the Supplement Facts panel, not only the sales copy, and note amounts per serving.
3. Check who the manufacturer, packer or distributor is, and whether an address or phone number is printed.
4. Ask what studies exist on the exact ingredients and doses.
5. Talk to a doctor or pharmacist if you take medicines, since the FDA warns some supplements can interact with them.

Browse our blood sugar category to see how pages in a crowded area word their claims, and see all our reviews for how the scoring works in practice.

FAQ

Is a dietary supplement a drug?

Not legally, unless it is marketed as one. The FDA says a product sold as a supplement but presented for treatment or prevention of a specific disease meets the definition of a drug. Generally, the supplement definition also excludes ingredients approved as new drugs.

Does the FDA test supplements before they are sold?

No. The FDA says it does not test supplements before they are sold and has limited resources to analyze their contents, so it focuses first on public health emergencies and products that may have caused injury or illness.

Why do supplement labels say the FDA has not evaluated the statement?

Because DSHEA requires that disclaimer whenever a label makes a structure/function claim, a claim about a classical nutrient deficiency disease, or a claim of general well-being. The FDA says these claims are not approved by the agency and do not require FDA evaluation before use.

Can a supplement interact with my medicine?

Yes, it can. The FDA says some supplements can interact with medications, interfere with lab tests, or have dangerous effects during surgery. Ask your pharmacist before starting one, and see our medical disclaimer for the limits of what a review site can tell you.