The Same Supplement Can Cost 31× More Per Day (2026 Data)
Key finding: Across 730 products in 116 supplement categories, the cost to take the same supplement every day varies up to 31.4× (Boswellia) depending on brand and form. And in 70% of categories (80 of 115), the cheapest product by sticker price is not the cheapest per day — because servings-per-container and dose-per-serving swing the real cost far more than the price on the bottle.
All figures are computed from our open dataset (CC BY 4.0), last price-verified August 25, 2026. Methodology below. If you cite these numbers, please link this page.
Cost-per-day spread, by supplement
For each category we take the lowest and highest cost per clinically-effective daily dose among the products we track, normalized to the active-ingredient amount studied in trials (not per pill, not per serving).
| Supplement | Cheapest / day | Most expensive / day | Spread |
|---|---|---|---|
| Boswellia | $0.07 | $2.20 | 31.4× |
| Ginseng | $0.11 | $3.42 | 31.1× |
| Cranberry | $0.06 | $1.44 | 24.0× |
| Garlic | $0.04 | $0.95 | 23.8× |
| Beetroot | $0.07 | $1.33 | 19.0× |
| Pine bark extract | $0.08 | $1.50 | 18.8× |
| Saw palmetto | $0.05 | $0.85 | 17.0× |
| Msm | $0.03 | $0.51 | 17.0× |
| Branched chain amino acids | $0.05 | $0.82 | 16.4× |
| Flaxseed oil | $0.06 | $0.91 | 15.2× |
| Betaine tmg | $0.07 | $1.00 | 14.3× |
| Vitamin e | $0.08 | $1.13 | 14.1× |
Download the data (CSV) · full category spread list, 115 categories
A concrete example: magnesium glycinate
The same form of magnesium, at the same elemental dose, runs from $0.18/day (BulkSupplements.com) to $0.87/day (Thorne) — a 4.8× gap. Over a year that is the difference between about $66 and $318 for the identical active ingredient.
Compare Magnesium Glycinate Products by Cost Per Day
The concrete example above, live: here's how every magnesium glycinate product we track actually compares.
| Product | Dose/Serving | Servings | Price | Cost/Day | Certification | Buy |
|---|---|---|---|---|---|---|
| BulkSupplements Magnesium Glycinate Powder Budget Pick | 225mg | 200 | $19.97 | $0.18 | None | Buy on Amazon |
| Vitamin Shoppe Magnesium Glycinate 400mg Best Value | 400mg | 90 | $19.99 | $0.23 | None | Buy on Amazon |
| Nature Made Magnesium Glycinate 200mg Quality Pick | 200mg | 60 | $11.20 | $0.36 | USP Verified | Buy on Amazon |
| Doctor's Best High Absorption Magnesium | 200mg | 60 | $13.99 | $0.46 | None | Buy on Amazon |
| KAL Magnesium Glycinate 400 | 400mg | 45 | $24.79 | $0.55 | None | Buy on Amazon |
| Thorne Magnesium Bisglycinate | 200mg | 60 | $26.00 | $0.87 | NSF Certified for Sport | Buy on Amazon |
Why the cheapest bottle usually isn't the cheapest supplement
Shoppers optimize for the number on the shelf, which is the wrong number. Two bottles at the same sticker price can differ 3–5× in real cost once you account for how many days each one lasts and how much active ingredient each dose delivers. In our data this happens in 70% of categories.
Methodology
- Cost per effective daily dose = price ÷ servings per container, normalized to the clinically-studied dose of the active ingredient.
- Prices are the current Amazon Buy Box price, refreshed via the Amazon Product Advertising API and last verified August 25, 2026.
- Ingredient doses and forms are from the NIH Dietary Supplement Label Database; clinical doses from PubMed. Full method on our methodology page.
- Reproducible from the public dataset (730 products, 116 categories, CC BY 4.0).