Labdoor Tests 36 Best-Selling Magnesium Supplements

SOUTH SAN FRANCISCO, CA – March 22, 2016 – Labdoor, the supplement testing and rating service, announces that their new Magnesium Rankings are now published online and ready to help consumers find the highest quality magnesium supplements on the market.

Labdoor tested 36 best-selling magnesium supplements for active and inactive ingredient content and heavy metal load. Only about half of all products measured magnesium levels within 5% of their label claims. Products measured magnesium content anywhere from 90.5% less than a label claim to 97.5% more with actual content ranging from 38.1 mg to 691.2 mg of magnesium per serving. 15 of 36 products measured at least 420 mg of magnesium per serving, the highest Recommended Dietary Allowance (RDA) for adults (in this case, male adults ages 31+).

More than half of the tested products exceeded 350 mg of magnesium per serving, the daily Tolerable Upper Intake Limit (UL) for adults. This UL applies only to supplemental magnesium, not magnesium from foods. Moderate excess can lead to nausea, diarrhea, and abdominal cramping. Extreme excess can cause health risks as severe as difficulty breathing, extreme hypotension, arrhythmias, and cardiac arrest.

In this batch analysis, total arsenic levels were a concern. Total arsenic can be separated into organic and inorganic arsenic parts. California’s Proposition 65 does not establish a Maximum Allowable Dose Level (MADL) for total arsenic; to assess product purity, California’s Office of Environmental Health Hazard Assessment (OEHHA) 2003 proposed MADL on the inorganic portion of arsenic (0.1 mcg per day) was used. In this report, 2 out of every 3 products measured total arsenic levels that were projected to exceed this proposed inorganic arsenic limit. Long-term exposure to arsenic can cause cancer and skin lesions. Arsenic has also been linked to developmental defects, cardiovascular disease, and neurotoxicity.

The United States Department of Agriculture (USDA) has estimated that 57% of the US population above the age of 2 is not meeting daily required levels of magnesium. In individuals with magnesium deficiencies, magnesium supplements have been found to mildly reduce heart disease risk, improve diabetic status, and possibly help muscle activity. Because magnesium also naturally acts within excitatory and inhibitory pathways of the brain, there is some evidence that magnesium supplements may can help with sleep and prevent migraines in magnesium-depleted people. Magnesium supplements have also been commonly used as laxatives and antacids, and as a component in treating osteoporosis in postmenopausal women.

Recent interest has grown in two areas of magnesium research, specifically with respect to brain injury and testosterone levels during athletic activity. Animal model studies have shown that magnesium supplements may induce protective benefits after traumatic brain injury, but research attempting to extrapolate data to human models has so far been negative. In research related to testosterone levels, both animal and human studies have been limited and overall lacking in results that show significant testosterone effects.

This new report from Labdoor is designed to help consumers find safe and effective magnesium 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.

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