Labdoor Tests 25 Best-Selling Green Tea Supplements

Green Tea

SOUTH SAN FRANCISCO, CA – January 6, 2016 – Labdoor, the supplement testing and rating service, announces that their new Green Tea Rankings are now published online and ready to help consumers find the highest quality green tea supplements on the market.

After water, tea is the most popular beverage in the world and green tea comprises 20% of worldwide tea consumption. Global annual sales of green tea supplements are on track to reach $368 million by 2020. The ubiquity of green tea consumption, however, underscores a number of scientific studies that have linked anti-inflammatory and antioxidant properties in green tea with preventing chronic diseases like cancer, diabetes, high cholesterol, liver disease, and obesity. Obesity itself cost the US $147 billion in 2008, and some research has promoted green tea as a relatively cheaper way to prevent and treat obesity and curtail the public health expense. Research is notably still inconclusive in many cases and the interactions between green tea compounds have not been fully clarified. For now, studies suggest that the main green tea compounds associated with weight loss, caffeine and epigallocatechin gallate (EGCG), work by increasing metabolic rate and fat oxidation and reducing fat production and absorption.

Labdoor tested 25 best-selling green tea supplements in the US using 250 analytical chemistry assays to measure active and inactive ingredients and determine whether products had harmful levels of heavy metals. The supplements in this batch had no standard method for labelling active ingredients and in some cases, cited proprietary blends with unspecified quantities of secondary ingredients, failing to provide transparency for harmful quantities of ingredients or levels of ingredients that were too little to even be effective. Products ranged from having only 21.4% of its label claim to having more than 3 times (306.3%) of its label claim for an active ingredient. Still, limited research suggests that health benefits from green tea extracts begin at daily doses of 140 mg of catechins, including EGCG, and accumulate with higher doses, and all but 4 products met this threshold in 1 serving.

Weight loss benefits of green tea have been found in research at doses of 270 mg of EGCG + 150 mg of caffeine. Applied Nutrition Green Tea Fat Burner was the product closest to this combination dosage with 373 mg and 146 mg of EGCG and caffeine per serving, respectively. All other products contained less than 70 mg of caffeine per serving. All but 8 products measured EGCG levels below 270 mg per serving.

Heavy metals were also an issue for this batch of products. 10 of the 25 products tested exceeded California Proposition 65 lead limits in 1-2 serving. 6 of those products also exceeded inorganic arsenic limits in 1-2 servings. In addition, Applied Nutrition Green Tea Fat Burner and Irwin Naturals Triple-Tea Fat Burner both used titanium dioxide, a whitening agent linked to cancer and Alzheimer’s disease. And Hoodia gordonii, a steroidal compound with dangerous potential for increasing blood pressure, heart rate, and markers of liver damage, was used in the formulation for Spring Valley Green Tea.

Bulk Supplements Green Tea Extract, Hard Rhino Green Tea Extract, and Nutrigold Decaffeinated Green Tea Gold ranked top 3 in terms of purity, safety, and meeting effective doses of active ingredients.

This new report from Labdoor is designed to help consumers find safe and effective green tea supplements. Labdoor publishes the data about each product’s key 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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