Labdoor Tests 30 Best-Selling Zinc Supplements

SOUTH SAN FRANCISCO, CA – February 23, 2016 – Labdoor, the supplement testing and rating service, announces that their new Zinc Rankings are now published online and ready to help consumers find the highest quality zinc supplements on the market.

For all the essential roles that zinc plays in our bodies, zinc is often unfortunately ignored in daily health conversations. Zinc is required for proper DNA synthesis, cell division, and cell turnover. For this reason, zinc deficiency is associated with stunted physical and mental development. Our immune system’s ability to fight infections and heal wounds also depends on zinc, without which, we become more susceptible to infectious diseases like pneumonia and diarrhea, and wounds from injury can become chronic ulcers. Zinc also has potential antioxidant activity, protects our eyes from damage, plays a role in our learning and behavior, and may even affect one’s risk for prostate cancer.

Research suggests that supplementing with zinc may enhance immune function, even helping with the length and severity of colds when zinc (as a lozenge or syrup) is taken within a day of symptoms beginning. Older patients who supplement with zinc may be able to lower risks for eye diseases like night blindness and advanced age-related macular degeneration when used in conjunction with other antioxidants. Zinc also has a few prescription uses like treating acne vulgaris, acrodermatitis, and childhood diarrhea especially in developing countries.

Labdoor tested 30 best-selling zinc supplements in the US using 210 analytical chemistry assays to measure active and inactive ingredients and determine whether products had harmful levels of heavy metals. Products were relatively accurate in their label claims. Measured zinc levels deviated an average of 4.4% from their respective label claims. 26 products measured at least 11 mg of zinc per serving, meeting the Recommended Dietary Allowances (RDAs) per day for adult males and nonpregnant females. 20 of 30 products measured more than 20 mg of zinc per serving even though research on absorption rates of zinc has found that further increasing zinc doses above 20 mg produces diminishing returns on absorption.

While zinc serving sizes generally seemed to meet dietary recommendations, they also tended to exceed established safety levels. 12 of 30 products measured zinc servings above the established Tolerable Upper Intake Level (UL) for zinc of 40 mg per day. Risks for acute excess include headaches, loss of appetite, nausea, abdominal cramps, and diarrhea. With chronic intake above the ULs, risks may increase for copper and/or iron deficiency, impaired immune responses, reduced levels of high-density lipoproteins (HDL cholesterol), and harmful changes to urinary physiology.

All products passed Labdoor’s heavy metal screens. Each product measured less than 2 PPM (parts per million) of arsenic, lead, bismuth, cadmium, silver, or antimony. 1 product, Trace Minerals Ionic Zinc, was found to contain potassium benzoate, a preservative that has been associated with some potential to cause cancer.

This new report from Labdoor is designed to help consumers find safe and effective zinc supplements. Labdoor publishes the data about each product’s active ingredients and potential contaminants on its website. “Quality” and “Value” rankings are also available for viewers to sort through and select products of interest.

For press inquiries, please email press@labdoor.com.