What’s really in your dietary supplement? Original paper

In an independent analysis of 57 dietary supplements, 84% did not contain the amount of ingredient claimed, 40% did not contain any of the ingredient claimed, and 12% contained undeclared ingredients prohibited by the FDA.

The contents of dietary supplements labeled as containing 1 of 5 components: Rauvolfia vomitoria extract, methylliberine, turkesterone (a type of ecdysteroid), halostachine, or octopamine.

57 dietary supplements (purchased online) containing Rauvolfia vomitoria extract (13 samples), methylliberine (21 samples), turkesterone (8 samples), halostachine (7 samples), or octopamine (8 samples).

Many of the supplements were labeled as useful for fat loss or as a preworkout product for improved exercise performance.

The investigators used high-performance liquid chromatography to examine the quantity of components in supplement samples. In addition to looking for the substances claimed on the label, the investigators analyzed the samples for 9,403 compounds that may be hidden or inadvertently included in dietary supplements.

Overall, of the 57 supplements analyzed, 23 (40%) contained no detectable amounts of the claimed ingredient, and only 9 (16%) contained close to the amount (i.e., within 10%) of the ingredient claimed on the label. Furthermore, 7 (12%) supplements contained ingredients prohibited by the FDA.

• Of the 13 supplements said to contain Rauvolfia vomitoria extract, all 13 contained no detectable amount of the extract, and 4 contained ingredients prohibited by the FDA.
• Of the 21 supplements said to contain methyllberine, 13 contained 10% more methyllberine than the label claimed (the highest contained 234% more), and 1 contained less methyllberine than the label claimed (39% less)
• Of the 8 supplements said to contain turkesterone, all 8 contained little or no turkesterone (the highest was 0.1 mg in a supplement claiming to contain 500 mg).
• Of the 7 supplements said to contain holostachine, all 7 contained little or no holostachine (the highest was 3 mg in a supplement claiming to contain 100 mg).
• Of the 8 supplements said to contain octopamine, 1 contained very little octopamine (0.2 mg), and 2 contained no detectable octopamine.

The FDA-prohibited ingredients identified were deterenol, oxilofrine, noopept, octodrine, and 1,4-DMAA.

The study investigators wrote in their conclusion that 89% of the supplements “did not accurately declare the ingredients found in the products”, based on the fact that 6 of 57 supplements contained within 10% of the amount of ingredient claimed on the label. However, only 38 supplements made claims about how much of the ingredient it contained, so we felt that 84% (6/38) was a more accurate value.