Keeping sleep-product claims inside DSHEA structure-function limits

A sleep supplement label can say a product "supports restful sleep." It cannot say the product "cures insomnia" or "fixes sleep apnea." That distinction is the entire game under the Dietary Supplement Health and Education Act of 1994, and most of the compliance failures I've seen in this category come from marketers who never internalized why that line exists in the first place.

DSHEA carved out a category of claims called structure/function claims. These are statements about how a nutrient or ingredient affects the normal structure or function of the human body: melatonin "helps maintain healthy sleep cycles," magnesium "supports muscle relaxation," L-theanine "promotes a calm mental state." What a supplement cannot do, under this same law, is claim to diagnose, treat, cure, mitigate, or prevent a disease. Insomnia is a disease. Sleep apnea is a disease. Restless leg syndrome, when framed as a clinical diagnosis, is a disease. The moment a label or a marketing claim ties a product to any of those terms, it has left the structure/function lane and entered drug-claim territory, and the FTC and FDA will treat it that way regardless of how the ingredient actually performs.

Why the Category Gets This Wrong So Often

Sleep is the supplement category most prone to overreach, and there's a reason for that. Poor sleep is miserable, universal, and easy to describe in disease terms because that's how people actually talk about it. Nobody tells a friend their "sleep cycle homeostasis is suboptimal." They say "I have insomnia." Copywriters pick up that language because it converts, and it converts precisely because it borrows the credibility of a medical diagnosis.

That borrowed credibility is what regulators are watching for. The FDA's guidance on structure/function claims (part of the framework established after DSHEA, and refined through subsequent guidance documents on notification requirements under 21 U.S.C. 343(r)(6)) draws the distinction based on whether the claim references a disease state by name, by clinical symptom, or by close synonym. Say "supports occasional sleeplessness" and you're likely fine. Say "relieves insomnia" and you've made a drug claim, because insomnia is a defined disorder in the DSM and in ICD coding, not a lifestyle inconvenience.

The Mechanism Companies Actually Get Tripped Up On

Here's where it gets granular, because the disease-claim trap isn't just about which noun you use. It's about the causal structure of the sentence.

A claim like "helps you fall asleep faster" is generally acceptable as a structure/function claim, because it describes an effect on a normal body function: sleep onset. A claim like "treats sleep onset insomnia" describes the same underlying biology but frames it as treatment of a diagnosed disorder. The FDA doesn't evaluate these two sentences on the chemistry. It evaluates them on the rhetoric. That's a hard pill for scientifically minded founders to swallow, because it means a company can have excellent clinical data on an ingredient and still get a warning letter for how it chose to describe that data.

This is also where implied disease claims sneak in, and companies underestimate how broadly FDA reads "implied." A product photographed next to a bottle of Ambien. A testimonial that says "I finally got off my prescription sleep aids thanks to this." A claim that a product works on "sleep apnea symptoms" even without using the word "cure." All three of these have shown up in FDA warning letters to supplement companies over the years, because the agency doesn't require an explicit disease name to conclude that a disease claim has been made. Context, imagery, and implication count.

The Required Disclaimer, and Why It's Not Decoration

Every structure/function claim on a supplement label has to carry the DSHEA disclaimer: "This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease." Companies treat this as boilerplate, something legal drops into the footer in six-point type. That's a mistake, because the disclaimer is doing real legal work; it's the mechanism by which a structure/function claim stays outside the definition of a drug claim under the Federal Food, Drug, and Cosmetic Act.

But the disclaimer doesn't launder a claim that's substantively a disease claim. You cannot say "cures insomnia" and then paste the disclaimer underneath and call it compliant. FDA has been explicit on this point in guidance and in enforcement actions: the disclaimer protects legitimate structure/function claims from being reclassified, it does not immunize actual disease claims. Marketers who think of the disclaimer as a shield rather than a technical requirement are the ones who end up on the receiving end of a warning letter.

Where Melatonin Sits, and Why It's a Special Case

Melatonin deserves its own mention because it occupies a strange spot in this framework. It's sold over the counter in the U.S. as a dietary supplement, unlike in much of Europe, where it's regulated as a medicine and available by prescription in many markets. That regulatory split exists because DSHEA classifies melatonin as a dietary ingredient rather than a drug, so long as companies market it using structure/function language rather than disease claims.

That means a U.S. melatonin brand can say its product "supports the body's natural sleep-wake cycle," which is a defensible structure/function claim describing melatonin's actual role in circadian regulation. It cannot say the product "resets your circadian rhythm disorder" if that phrase is meant to describe a diagnosed condition like delayed sleep phase disorder, because now it's making a claim about treating a recognized medical condition rather than describing normal physiology.

The Practical Test Worth Running on Every Claim

Ask whether the sentence would still make sense if you replaced the health outcome with a disease name. "Helps support healthy sleep patterns" cannot be rewritten as "treats disease X" without changing its meaning, because it's genuinely describing a function, not a cure. "Relieves symptoms of insomnia" can be rewritten that way trivially, because insomnia is already sitting inside the sentence.

Companies that run this test on every label claim and every marketing sentence, including the ones on Instagram captions and Amazon bullet points, catch most of their own violations before a regulator does. The ones that skip this step, because the copy tested well or the founder liked how it sounded, are the ones writing response letters to the FDA a year later.

None of this is a knock on the sleep supplement industry, which includes companies doing careful, well-substantiated work within these boundaries. It's a reminder that the boundaries are load-bearing, not cosmetic, and that DSHEA's structure/function framework, for all its limits, is the reason this category can exist on store shelves without a prescription at all.