There's a free, government-run database that contains the labels of over 178,000 dietary supplements — every ingredient, every dose, fully searchable. It's run by the National Institutes of Health, it's completely public, and almost nobody outside the research world knows it exists.
It's called the Dietary Supplement Label Database (DSLD), and it's one of the most useful and least-used resources in consumer health. Here's what it is and how to actually get value from it.
What the DSLD actually is
The DSLD is maintained by the NIH Office of Dietary Supplements. It catalogs the full label information of dietary supplement products sold in the United States — the active ingredients, the amounts, the serving sizes, the other ingredients, the marketed claims. Think of it as a giant, neutral reference of what's actually in the products on the shelf, straight from the labels themselves.
Crucially, it's not trying to sell you anything. It's a reference, not a store. There are no affiliate links, no "buy now" buttons, no sponsored rankings. Just data.
Almost every other place you can look up a supplement is trying to sell it to you. The DSLD is one of the few neutral, comprehensive sources — funded by the public, owned by no brand.
What you can use it for
- Decode a label. Look up a product and see its full ingredient breakdown — useful when a "proprietary blend" hides the actual amounts.
- Compare products. See how two similar products actually differ on ingredients and doses, rather than on marketing.
- Check a dose against guidelines. Cross-reference a product's amount of a nutrient against NIH's recommended intakes and upper limits.
- Spot hidden overlap. Find out which of your products contain the same ingredient — the root cause of most supplement waste.
The catch: it's built for researchers, not shoppers
Here's the honest limitation. The DSLD is a phenomenal dataset, but the interface is built for professionals. You can search a product and read its label, but it won't tell you "these two things you take conflict" or "you're over the upper limit on zinc." It gives you the raw facts; the interpretation is on you.
So if you want to use it to audit your own stack, you'd be doing a lot of manual cross-referencing: looking up each product, noting each ingredient and dose, checking each against intake guidelines, and comparing everything against everything else. Powerful, but slow.
Unpill is built directly on the NIH DSLD. You enter what you take, and it does the cross-referencing for you — flagging redundancies, absorption conflicts, and upper-limit issues automatically. Free, no signup, about 60 seconds.
Audit my stack — free →Same NIH data. We just make it readable. We earn nothing when you buy supplements.
The bottom line
The DSLD proves something worth remembering: good, neutral supplement information exists and is free. You don't have to rely on the brand selling you the product or the influencer earning a commission on it. Whether you dig through the database yourself or use a tool built on top of it, the goal is the same — decisions based on data, not marketing.