Zinc supplements are often promoted for immune and other health benefits, but their effectiveness depends on dosages aligned with clinical studies. Consumerlab.com’s survey of popular retail zinc supplements revealed that while all products met labeled zinc amounts and had acceptable lead levels, only one of four immune-marketed lozenges provided a dosage comparable to research-backed immune benefits.
All tested products met quality standards, but Consumerlab highlighted significant differences in cost and dosage relative to subcategories like immune health. For 50 mg zinc doses, prices varied widely from 3 cents to over 18 cents, especially for products with additional ingredients. The most common dosage among zinc supplements (liquids and pills) was about 50 mg/day, exceeding the Upper Tolerable Intake Level of 40 mg/day. This dose aligns with research on zinc deficiency and high-dose approaches for conditions like acne, depression, and anorexia nervosa. Dosage comparisons extended to vision studies, such as the Age-Related Eye Disease Study (AREDS), which includes zinc (80 mg) and antioxidants. Two eye health products met AREDS dosage levels, with one costing 30% less than the other. Dr. Tod Cooperman, president of Consumerlab.com, emphasized that not all supplements provide proven effective dosages. He advised consumers to choose products with correct dosages for specific uses and avoid long-term excessive zinc intake due to risks like reduced copper absorption and immune suppression. For full testing details and product names, visit Consumerlab.com (registration with fee required).
