Dietary supplements in the United States are regulated, but not the way most people assume. FDA does not approve them before they go on sale. The legal burden of making a safe, accurately labeled product sits with the company that makes it, and FDA acts mainly after a product is already on the market.
That framework is neither a scandal nor a free-for-all. It has specific rules, specific enforcement powers and specific, well-documented failure points. Knowing where those failure points are is the difference between buying carefully and buying anxiously.
What DSHEA actually did
The Dietary Supplement Health and Education Act of 1994 amended the Federal Food, Drug, and Cosmetic Act to create a separate category for supplements, distinct from both food and drugs. FDA’s own summary is unambiguous: under DSHEA, FDA does not have the authority to approve dietary supplements before they are marketed, and a firm generally does not have to give FDA the evidence it relies on for safety, before or after launch.
There are real obligations behind that. Facilities that manufacture, process, pack or hold supplements must register with FDA. A product containing a new dietary ingredient — one not marketed in the US before 15 October 1994 — requires a notification to FDA at least 75 days before it enters commerce. Firms making structure-function claims must hold substantiation that the claim is truthful and not misleading. And a firm is responsible for ensuring its products are not adulterated or misbranded.
What is absent is a pre-market gate. No agency checks the bottle before you can buy it.
cGMP: the rule that does most of the work
The substantive quality rule is 21 CFR Part 111, current good manufacturing practice for dietary supplements, in force since 2007. It requires written specifications for identity, purity, strength and composition; qualification of suppliers; controlled production and process records; a quality unit with authority to reject material; and handling of complaints and returns.
The provision that matters most to a buyer is §111.75, which requires the manufacturer to verify by testing that specifications are actually met, including identity testing on incoming dietary ingredients. In practice this is what stops the wrong plant species, or a cheaper substitute, from ending up in a capsule.
cGMP is a process standard, not a proof of efficacy. A product can be made in full compliance with Part 111 and still do nothing useful. Compliance means the contents match the label and the plant is controlled. That is worth a great deal, and it is not the same as the product working.
What inspections have found
FDA inspects supplement facilities and publishes the results as inspection observations and warning letters. The picture is not reassuring at the industry level. A 2016 review in Drug Testing and Analysis reported that FDA inspections had revealed good manufacturing practice violations in over half of the facilities inspected, including unsanitary conditions and a lack of product specifications.
That figure deserves context in both directions. Inspections are not a random sample — FDA targets, and problem firms attract repeat visits — so it is not a clean estimate of the whole industry. It is still a large number, and it is the single best reason to care whether a specific manufacturer has been inspected and what was found.
Where adulteration is concentrated
Deliberate adulteration with pharmaceuticals is a genuine problem, and it is concentrated in three product categories. A 2018 analysis in JAMA Network Open examined FDA’s tainted-products database and found 776 adulterated dietary supplements identified between 2007 and 2016, implicating 146 companies.
The breakdown is the useful part. Of those 776 products, 45.5% were marketed for sexual enhancement, 40.9% for weight loss and 11.9% for muscle building. Sibutramine, a withdrawn weight-loss drug, was found in 84.9% of the adulterated weight-loss products. Synthetic steroids or steroid-like ingredients were in 89.1% of the adulterated muscle-building products. Twenty-eight products were named in more than one warning, and most of those were found to contain new undeclared ingredients the second time.
Almost the entire adulteration problem lives in those three categories. FDA maintains a public list of tainted products, and checking it before buying anything sold for weight loss, sexual performance or muscle building is the highest-value five minutes a supplement buyer can spend.
Adverse events and how they are counted
Since 2006, manufacturers have been legally required to report serious adverse events associated with their products to FDA, and consumers and clinicians can report directly through FDA’s reporting route. Reports feed the CFSAN Adverse Event Reporting System.
The best population estimate came from a 2015 study in The New England Journal of Medicine using surveillance data from 63 emergency departments over ten years. It estimated 23,005 emergency department visits per year in the US attributed to adverse events related to dietary supplements, resulting in about 2,154 hospitalizations. Weight-loss and energy products accounted for 71.8% of the supplement-related visits involving palpitations, chest pain or tachycardia, and those visits skewed heavily toward adults aged 20 to 34. Among older adults, the commonest problem was swallowing difficulty, often with micronutrient pills.
Two conclusions follow. The risk is real and measurable. It is also overwhelmingly concentrated in stimulant-containing weight-loss and energy products rather than in vitamins, minerals or food-form powders.
What third-party certification does and does not verify
Independent certification programs fill part of the gap left by the absence of pre-market approval. They are not equivalent to each other, and none of them tests whether a product works.
| Program | What it primarily verifies |
|---|---|
| USP Verified | Ingredient identity and potency, contaminant limits, dissolution, and an audit of manufacturing against GMP |
| NSF Certified for Sport | Label accuracy and contaminant limits, plus screening for substances banned in sport |
| Informed Sport | Batch-by-batch testing for substances banned in sport |
| cGMP audit certification | That the facility’s processes and records meet the Part 111 standard |
USP’s dietary supplement verification program covers auditing, review and testing of finished products. NSF Certified for Sport is built around banned-substance screening for athletes. A seal on a package means the specific product was in the program at some point; the programs publish searchable listings, and checking the listing rather than trusting the printed mark is the correct habit.
Where the marketing usually goes wrong
The commonest failure is not contamination. It is claims. FTC’s Health Products Compliance Guidance replaced the 1998 advertising guide and notes that since then the agency has settled or adjudicated more than 200 cases involving false or misleading claims about health-related products.
A supplement may not claim to prevent, treat, cure or reduce the risk of a disease — that is a drug claim. Structure-function statements are permitted, and must be substantiated. The practical signal for a reader is simple: a product page that names diseases is either breaking the rules or hoping you will not notice the disclaimer. A product page that describes what the ingredient is, what the evidence found and where it is thin is behaving.
An earlier version of this page argued that our products were safe because they are “100% natural.” That is not a safety argument. Ephedra was natural, and comfrey and kava, both named in the article we were responding to, are natural. Natural describes origin, not risk, and we should not have used it that way.
How to evaluate any brand, including this one
Six checks, in order of usefulness.
- Category first. Weight-loss, sexual-enhancement and muscle-building products carry almost all the documented adulteration risk. Treat them differently from a vitamin or a food powder.
- Search FDA’s tainted-products list for the product and the company name.
- Ask for a certificate of analysis for the lot you are buying. A firm that tests to specification has these and can send one.
- Check the seal in the certifier’s own registry, not on the package.
- Read the label for amounts. Proprietary blends that give a total without per-ingredient amounts make it impossible to compare a serving with any published research.
- Read the claims. Disease language, before-and-after imagery and “clinically proven” without a citation are all reasons to slow down.
Two facts about our own company that we can state and that you are entitled to weigh: Greens Plus has never had a product recalled, and all of its products currently hold cGMP certification. Neither of those is a claim about what the products do, and we are not going to dress them up as one.
Common questions
Does FDA approve dietary supplements?
No. Under DSHEA, FDA has no authority to approve supplements before they are marketed, and it generally does not review claims before use. Manufacturers are responsible for safety and labeling, and FDA acts after products reach the market.
What does cGMP certification actually mean?
It means a facility’s processes, records and testing have been audited against 21 CFR Part 111, which requires written specifications and verification by testing that they are met. It is evidence that what is in the container matches the label. It is not evidence that the product has a health effect.
Which supplements are most likely to be adulterated?
Products sold for weight loss, sexual enhancement and muscle building. Those three categories accounted for more than 98% of the 776 adulterated supplements FDA identified between 2007 and 2016.
Is a third-party seal enough on its own?
It is a strong signal, but verify it. Programs differ in what they test — some check identity and contaminants, some focus on substances banned in sport, none tests efficacy. Look the product up in the certifier’s public listing rather than trusting the printed mark.
How do I report a bad reaction to a supplement?
Tell your clinician first, then file a report with FDA through its dietary supplement reporting route. Serious adverse events are also required to be reported by the manufacturer, and consumer reports are what make patterns visible.
The honest summary of US supplement regulation is that the rules are real, the enforcement is retrospective, and the risk is unevenly distributed across categories. A careful buyer can eliminate most of it by avoiding the three high-risk categories and verifying manufacturing rather than trusting marketing.
How we approach sourcing and formulation, and what is in each product, is documented at Greens Plus, and the label-reading side of the same question is covered in our guide to choosing a greens powder and in the company’s own history.
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