180 analytical tests on 20 best-selling vitamin D supplements in the United States.
All 20 vitamin D supplements exceeded their claimed vitamin D3 content, averaging 23% over their stated label claims.
There is no established upper limit for label claim variance for nutrients like vitamin D under US law. The only requirement is that these nutrients must be present at 100% or more of the value declared on the label.
Labdoor analyzed 20 best-selling vitamin D supplements in the United States for vitamin D3 content, heavy metal contamination, and presence/absence of GMO events.
All 20 products exceeded their claimed vitamin D3 content, averaging 23% over their stated label claims. 6 of the 20 products exceeded their label claims by greater than 40%.
Additionally, all products recorded at least 1000 IU vitamin D per serving, significantly above vitamin D's 400 IU Daily Value (DV) and its 600 IU Recommended Dietary Allowance (RDA).
All supplements passed their heavy metals and GMO assays.
6 of the 20 products in this report exceeded their label claims by greater than 40%.
All 20 vitamin D supplements tested in this batch passed heavy metal screens for arsenic, lead, cadmium, bismuth, antimony, and silver (below 1 PPM).
The Recommended Dietary Allowance (RDA) is set at 600 IU per day for most adults. For people over 70 years old, the IOM recommends an increased RDA of 800 IU per day.
Clinical studies indicate that toxicity is unlikely to occur at the 1000-2000 IU dosages of vitamin D commonly found in dietary supplements.
Every vitamin D supplement analyzed for this report utilized vitamin D3 (cholecalciferol) instead of vitamin D2 (ergocalciferol).