Liver biomarkers in adults: Evaluation of associations with reported green tea consumption and use of green tea supplements in U.S. NHANES.

Some events of hepatotoxicity have been linked to consumption of green tea supplements. The association between consumption of green tea or green tea supplements and abnormal liver biomarkers in adults was investigated using cross-sectional data from the 2009-2014 United States National Health and Nutrition Examination Survey (U.S. NHANES). Individuals with levels of either bilirubin or GGT, ALT, AST, and/or ALP in excess of the age- and gender-specific upper limits of normal ranges were classified as having abnormal liver biomarkers. Associations between green tea or green tea supplement use (consumption vs. not) and liver function were determined using multiple logistic regression modelling. 12,289 persons were included in the green tea analyses and 12,274 in the green tea supplement analyses. The odds of having one or more abnormal liver biomarkers were significantly reduced (p = 0.01) with consumption of green tea (OR: 0.49; 95% CI: 0.28, 0.85), while no significant association (p = 0.78) was determined for consumption of green tea supplements (OR: 0.92; 95% CI: 0.52, 1.64). Based on data from the 2009-2014 U.S. NHANES, green tea consumption was associated with reduced odds of having one or more abnormal liver biomarkers; whereas, no significant association was determined with consumption of green tea supplements.

Absence of genotoxicity of purified Aloe vera whole leaf dry juice as assessed by an in vitro mouse lymphoma tk assay and an in vivo comet assay in male F344 rats.

Hydroxyanthracene derivatives (HAD) are naturally present in the latex layer of Aloe vera leaf, predominantly as aloins A, B and aloe-emodin. HAD are typically removed from commercial ingestible aloe products through activated charcoal filtration (decolorization). Current research aimed to evaluate genotoxic potential of a purified aloe whole leaf dry juice containing 0.3 ppm of total aloins and non-detectable aloe-emodin (LOD =0.01 ppm) in the L5178Y mouse lymphoma assay (MLA; OECD 490) and in vivo comet assay (OECD 489). No marked increases in mutant frequency at the tk locus were observed in the MLA at concentrations up to 5000 µg/mL for 3 h and 24 h (-S9), and up to a precipitating concentration of 3000 µg/mL for 3 h (+S9) compared to concurrent vehicle control. Relative total growth at the highest analyzable concentrations at 3 h (±S9) and 24 h (-S9) ranged from 64 to 133 %. In the comet assay, no statistically significant increases in DNA strand breaks were detected in the colon or kidney following oral gavage of 500, 1000 or 2000 mg/kg/day in male F344 rats for 2 days compared to concurrent vehicle control. Overall, these findings demonstrated the test article containing minimal HAD is not genotoxic under the described experimental conditions.

Review of usnic acid and Usnea barbata toxicity.

Usnic acid is a prominent secondary lichen metabolite that has been used for various purposes worldwide. Crude extracts of usnic acid or pure usnic acid have been marketed in the United States as dietary supplements to aid in weight loss. The US Food and Drug Administration (FDA) received 21 reports of liver toxicity related to the ingestion of dietary supplements that contain usnic acid. This prompted the FDA to issue a warning about one such supplement, LipoKinetix, in 2001 (http://www.cfsan.fda.gov/~dms/ds-lipo.html). Subsequently, usnic acid and Usnea barbata lichen were nominated by the National Toxicology Program (NTP) for toxicity evaluations. At present, a toxicological evaluation of usnic acid is being conducted by the NTP. This review focuses on the recent findings of usnic acid-induced toxicities and their underlying mechanisms of action.

A correction of misinformation regarding Herbalife.

The authors of the subject article by Senadhi et al have misrepresented the safety and regulatory status of Herbalife's products. While we are very concerned with the unwarranted and unfavorable publicity that the inaccuracies listed could generate for Herbalife, we would welcome any inquiries that these authors may have to better clarify our commitment to the safety and quality of our products as has been demonstrated in part by our ability to establish positive relationships with regulatory authorities worldwide through continued cooperation and compliance. This letter clarifies the misinformation presented about Herbalife in the subject article.