Data Sources

All data comes from the NIH Office of Dietary Supplements, Dietary Supplement Label Database (DSLD), the most comprehensive federal database of dietary supplement label information available to the public. The DSLD is maintained by the NIH Office of Dietary Supplements, which operates under the National Institutes of Health within the U.S. Department of Health and Human Services. The database contains label information from thousands of dietary supplement products marketed in the United States. Per-ingredient context, including dosing thresholds and deficiency narrative, references the NIH ODS Health Professional Fact Sheets for each nutrient (RDA, UL, deficiency, drug interactions).

Regulatory context throughout the site follows the Dietary Supplement Health and Education Act (DSHEA), 1994, 21 U.S.C. § 321(ff), Supplement Facts panel labeling rules in FDA 21 CFR 101.36, and Daily Value framing references FDA 21 CFR 101.9, Reference Daily Intake (RDI) values. Naturally-occurring nutrient context cross-references USDA FoodData Central.

The DSLD captures label data as submitted to or collected by NIH researchers, including complete ingredient lists, serving sizes, daily value percentages, manufacturer and brand details, product categories, and other label-declared information. This data represents what manufacturers print on their Supplement Facts panels.

Processing Pipeline

We download the NIH DSLD data export and process each product record as follows to transform raw label data into searchable, comparable supplement profiles:

• Parses product records: Extracts product name, brand, UPC, serving size, and serving unit from each DSLD entry.
• Extracts ingredients: Parses the Supplement Facts panel to identify active ingredients with their amounts per serving and units of measurement.
• Normalizes ingredient names: Standardizes common ingredient names (e.g., "Vitamin C" and "Ascorbic Acid" are linked) to enable cross-product comparison.
• Builds brand profiles: Aggregates all products under each brand for brand-level views.
• Builds ingredient profiles: Aggregates all products containing each ingredient for ingredient-level comparison views.
• Computes rankings: Within categories (multivitamins, omega-3s, probiotics, etc.) products are ranked by ingredient completeness and potency based on labeled amounts.

What We Do Not Do

PlainVitamins is strictly a data presentation portal. We maintain clear boundaries about what our platform does and does not provide:

• We do not independently test supplement products for actual ingredient content or purity.
• We do not evaluate supplement efficacy, safety, or health claims made by manufacturers.
• We do not recommend supplements for any health condition or nutritional purpose.
• We do not modify ingredient data from what is declared on the product label as cataloged in the DSLD.

Limitations

• The DSLD catalogs label data at the time of entry. Formulations shown may not reflect a manufacturer's current product.
• Not all dietary supplements marketed in the US are in the DSLD, coverage is comprehensive but not exhaustive.
• Rankings and comparisons are based on labeled amounts, not independent laboratory verification.
• Serving size standardization is complex, direct comparisons across products with different serving sizes require care.

Data Collection Method

The NIH DSLD collects label data from dietary supplement products through a combination of methods: direct collection from store shelves, manufacturer submissions, and research surveys. Each product entry captures the information exactly as printed on the Supplement Facts panel, including serving size, ingredient amounts, daily value percentages, and "other ingredients" lists. The DSLD does not verify whether actual product contents match label claims, that function falls under FDA enforcement authority. Our database reflects the label data as cataloged by NIH.

Update Schedule

The NIH DSLD is updated on a rolling basis as new product labels are collected and entered. We refresh our database periodically from the latest DSLD data export. Between updates, newly cataloged products will not appear in our database. Products that have been reformulated or discontinued by their manufacturer may still appear with their original label data until the DSLD entry is updated.

Corrections & Editorial Standards

Our full editorial & corrections policy explains how pages are produced, our sourcing standards, and exactly how to report a figure that looks wrong, including the dedicated address corrections@plainvitamins.com. For how to use supplement label data responsibly, see our health & appropriate-use disclaimer.

Not Affiliated

PlainVitamins is not affiliated with the NIH, the Office of Dietary Supplements, or any supplement manufacturer. We are an independent portal making NIH DSLD data more accessible.