| Popis: |
OBJECTIVES: Multi-ingredient dietary supplements (DSs) containing green tea (GT) were analyzed for their phytochemical content (seven catechins and caffeine) as part of a Dietary Supplement Ingredient Database project. The label information required by FDA is the weight of the GT extract or leaf powder, unless it is part of a proprietary blend (only the blend weight needed). Any information about the concentration of GT phytochemicals is voluntary. We assessed the accuracy of the mandatory and voluntary portions of labels and the effect of proprietary blends on the phytochemical content. METHODS: Two lots of 37 GT DSs, estimated to contain ≥40 mg/serving of GT, were purchased in a variety of market channels. Samples were sent for analysis to two experienced laboratories. Means and standard errors for the analytically measured content of epigallocatechin gallate (EGCG; the most prevalent catechin), the summed content of the catechins (total catechins, TC), and caffeine were derived for each DS and compared to label information. RESULTS: The measured content of EGCG, TC, and caffeine showed wide ranges (0 (not detected) - 442, 0–711, and 0–982 mg/day, respectively). DSs with concentration claims for EGCG and caffeine (32% and 43%, respectively) had higher content per serving compared to DSs without such information (P |
