Labdoor analyzed 27 best-selling calcium supplements in the United States. Analytics tests measured levels of calcium as well as heavy metal contaminants (antimony, arsenic, bismuth, cadmium, and silver).
Calcium products fared well in terms of label accuracy, with 18 products recording calcium content within 10% of their claims. Our analysis did find products ranging from 43% less to 28% more calcium than claimed on the label. On average, products recorded 3.7 more calcium than claimed on the label. In general, products were more likely to record more calcium than claimed. Sixty-seven percent (18) of the category recorded more calcium than claimed on their label.
All products in this report were screened by Inductively Coupled Plasma (ICP)-based techniques for the presence of heavy metals. Samples of each product passed all six heavy metals assays, indicating that samples contained under 2 PPM (part per million) each of arsenic, lead, cadmium, bismuth, antimony, and silver compounds.