Look Up Any Supplement

By Erin Rose · Updated March 16, 2026 · Powered by NIH DSLD · Methodology

Dietary Supplement Label Database Lookup

What is the NIH DSLD?

The Dietary Supplement Label Database (DSLD) is maintained by the NIH Office of Dietary Supplements. It contains label information for over 207,000 dietary supplement products sold in the United States. The data includes:

• Product name and brand
• All ingredients with exact forms (e.g., "Magnesium as Magnesium Glycinate")
• Quantities per serving
• Serving size and servings per container
• Daily Value percentages
• Other ingredients (fillers, binders, coatings)
• Structure/function claims
• Market status (on/off market)

What we found reading 12,081 of these labels

Searching one product tells you about one product. We have also read this database in bulk — pulling every label we could for 12 supplement categories and parsing the Supplement Facts panel off each one, so the question becomes what the shelf looks like as a whole rather than what one bottle contains.

Where labels sit against the safe ceiling

Only 3 of the 12 categories have a tolerable upper intake level set at all — for creatine, ashwagandha or berberine there is no official ceiling to measure against, and quoting a percentage would invent a standard that does not exist. Where a limit does exist, this is how the labels fall:

Read the magnesium row carefully, because the number looks worse than it is. Magnesium is the one case here where the upper limit sits below the recommended intake — 350 mg against an RDA of 320–420 mg. That is not a contradiction: the limit applies to magnesium from supplements, while the RDA counts what you eat as well, and it is set on the laxative effect rather than on toxicity. A 400 mg magnesium capsule is above the supplemental ceiling and is also an ordinary product.

Vitamin D and iron carry no such asterisk. Their limits are set on harm, they sit well above the recommended intake, and 18% and 8% of labels respectively still reach them — which is worth knowing before you take one every day for a year without testing.

The categories we have read so far

Each of these has its own write-up with the full distribution, the method, and what the sample cannot tell you.

Method: labels pulled from the NIH Dietary Supplement Label Database and read at the Supplement Facts panel rather than off the product name, because a name only carries a number when the brand chose to put one there. Most recent retrieval 2026-09-16. What this cannot tell you: how many bottles of anything are actually sold. It is a census of labels on the market, not of what people take, so read every share above as what is on offer rather than what is consumed.

How We Add Value

The raw DSLD data tells you what's in a product. We tell you if it's any good. Our tool layers quality analysis on top of the government data:

• Form quality: Is this a well-absorbed form? Magnesium glycinate vs oxide, D3 vs D2, TG vs EE fish oil.
• Dose adequacy: Does the amount per serving match what clinical trials actually used?
• Value analysis: What does this cost per studied dose compared to alternatives?

For a full quality audit with specific recommendations: Check Your Supplement →

For a personalized stack based on your goals: Supplement Recommender →

Frequently Asked Questions

Related Tools

• Check Your Supplement — Full quality audit with A/B/C/F grade and better alternatives
• Supplement Recommender — Personalized stack based on your goals
• Magnesium Forms Compared
• Vitamin D2 vs D3
• Fish Oil: TG vs EE