Guide · October 7, 2026
How to read a proprietary blend on a supplement label
One weight for five ingredients: what the rule allows and what the order tells you.
What the rule allows
A Supplement Facts panel normally prints the amount of every dietary ingredient per serving. A proprietary blend is the exception, and the Food and Drug Administration spells it out.
So a maker may group ingredients under one name and print one total. The individual amounts stay private.
The Supplement Facts panel must list the serving size and number of servings per container, declare each dietary ingredient in the product, and except for dietary ingredients that are part of a proprietary blend, provide information on the amount of the dietary ingredient per serving.
What the Prostacor panel prints
Prostacor's panel does exactly that. One line reads "Prostacor Proprietary Blend" with 351 mg beside it, and five ingredients follow.
Two of them carry a standard. The saw palmetto extract is marked 25% fatty acids, and the phytosterol complex is marked 40-45% beta sitosterol.
Supplement Facts
Serving Size: 1 Vegetable Capsule
Servings Per Container: 30
Amount Per Serving%DV
Prostacor Proprietary Blend351 mg†
- Saw Palmetto Extract (berry) (25% fatty acids)
- Phytosterol Complex (40-45% beta sitosterol)
- Stinging Nettle
- Pumpkin Seed
- Lycopene
† Daily Value not established.
Other Ingredients: Vegetable Capsule, Dicalcium Phosphate, Magnesium Stearate and Silica.
What the order tells you
Ingredients in a blend are listed by weight, heaviest first. On this panel saw palmetto extract comes first and lycopene last.
With five ingredients sharing 351 mg, simple arithmetic sets some limits. The first ingredient must weigh at least a fifth of the total, about 70 mg. The last can weigh no more than a fifth.
| Place on the panel | Ingredient | What the order allows |
|---|---|---|
| 1 | Saw palmetto | At least 70 mg |
| 2 | Beta-sitosterol | No more than 175 mg |
| 3 | Stinging nettle | No more than 117 mg |
| 4 | Pumpkin seed | No more than 87 mg |
| 5 | Lycopene | No more than 70 mg |
Why it matters for comparing products
Studies of these ingredients report their doses. One large pumpkin seed study gave men 5 grams of seed twice a day, more than 14 times the weight of a whole Prostacor capsule's blend.
Without printed amounts you cannot line a blend up against a study or against another brand. A single-ingredient product makes that comparison possible.
What a label is and is not
The supplements office at the NIH describes the panel's job in one sentence.
The same office notes that a quality seal on a bottle has limits of its own.
Products sold as dietary supplements come with a Supplement Facts label that lists the active ingredients, the amount per serving (dose), and other ingredients, such as fillers, binders, and flavorings.
These seals do not guarantee that a product is safe or effective.
Sources
- U.S. Food and Drug Administration: Questions and Answers on Dietary Supplements read 7 October 2026
- NIH Office of Dietary Supplements: Dietary Supplements: What You Need to Know read 7 October 2026
General information, not medical advice. Talk to a doctor or pharmacist before you start a supplement.