Product Review:Zinc Supplements (Including Pills, Liquids, Lozenges, and Vision Formulas)
HOW PRODUCTS WERE EVALUATED:
How Products were Selected: Products were selected to represent those commonly sold and/or available nationally in the U.S. ConsumerLab.com purchased products on the open market through retail stores, on-line retailers, and direct sales or multi-level marketing companies. Products were not accepted directly from manufacturers.
Testing Method: Zinc products were each tested for their elemental zinc content and possible contamination with lead. Analyses for zinc and lead were performed using ICP-MS (Inductively Coupled Plasma-Mass Spectroscopy).
Disintegration of non-chewable, non-capsule, non-enteric coated and non-time release formulations was analyzed by ConsumerLab.com utilizing USP (United States Pharmacopeia) <2040> methodology.
Products failing to meet any Passing Score were re-tested in a second independent laboratory using similar methods and instrumentation.
ConsumerLab.com may modify or use other appropriate test methods if necessary to test special product formulations.
Passing Score: * To achieve a "Pass" in the testing, a product had to:
Contain a minimum of 100% of its labeled amount of elemental zinc and not exceed 150% of this amount.
Not exceed California Prop 65 levels for lead contamination in a recommended daily serving of a dietary supplement, i.e., contain less than 0.5 mcg of lead per daily serving with an additional allowance of 1.0 mcg for supplements containing 1,000 mg/day or more of elemental calcium and 0.5 mcg for supplements containing specific other minerals.** For supplements not marketed for use by children, ConsumerLab.com provides an additional allowance of 0.5 mcg if containing 250 to 499 mg/day of elemental calcium, or 1.0 mcg if containing 500 to 999 mg/day of elemental calcium, and an allowance of 0.5 mcg if containing one whole herb (not extract) ingredient or 1.0 mcg for two or more whole herb ingredients. If a maximum recommended daily serving is not defined, a daily serving size will be determined and applied by CL.
Meet recommended USP parameters for disintegration for dietary supplements (excluding capsule, enteric coated, chewable and time-release products).
Meet FDA labeling requirements.
Passing scores allow for specific margins of technical error associated with each analysis. ConsumerLab.com reserves the right to disqualify a product at any time from passing its testing if it considers such product to present a safety risk or to provide misleading or inaccurate information in its labeling.
** Based on State of California's Prop 65 lead limit. California requires supplements exceeding this limit to bear a warning label regarding lead.
