SuppVersity - Nutrition and Exercise Science for Everyone

Image 1: Bought in bulk, grape-seed extract is actually reasonably cheap... and it does not even taste as awful as some other herb / seed extracts ;-) After initially being hailed as the yet another anti-oxidant panaceum, grape-seed extract (GSE) has been displaced by newer, fancier "superfoods" from the headlines of the major health and wellness newscasters. Therefore, even you, as a highly self-educated student of the SuppVersity could have missed out on a handful of recently released studies which reported antiviral effects of GSE ( Su. 2011 ) and confirmed its ameliorative effect on diet-induced obesity ( Ohyama. 2011 ) and (high) fructose-induced insulin resistance ( Meeprom. 2011 ). Moreover, a meta-analysis of nine controlled with more than 300 human subjects and daily doses ranging from 250mg to 2,000mg of GSE, which was published in the Journal of the American Dietetic Association ( Feringa. 2011 ), found that ... [b]ased on the currently available literature...

Image 1: Rat & guinea pig. Both very popular animal models. Both about the same size and weight, but with very different reactions to identical treatments. I won't waste too many words on this being a new series on the SuppVersity , I suppose the name "Ask Dr. Andro" is self-explanatory. It is based on questions posted in the comment section that are relevant for the majority of the visitors and require and deserve a more sophisticated response. So, if you want your question answered, learn a lesson from "Learner" who posted the following question in the comment section of " Spicing Up Fat Loss: Structural Similarity to Melanocortin-4 Agonists Powers Piperine's (Black Pepper Extract) Fat Loss and Lipid Lowering Effects ". Question from "Learner" : Why is the mg/kg dosing ratio different for humans than rats, and does that vary by the agent? Answer from Dr. Andro : Most of what we know about the effects of (new) drugs, ...

Regular visitors of the SuppVersity know about the diverse positive effects of dietary taurine on health, body composition and exercise performance. Now, a recent study by Mesallamy et al. ( Mesallamy. 2010 ) found another good reason for the non fish-eaters among you (fish is particularly high in taurine) some supplemental taurine in your diet / supplement regimens. Figure 1: Effect of HFD and taurine supplementation on weight gain at days 0 and 35 of feeding. Each value is expressed in grams. ( Mesallamy. 2010. Fig. 1 ) The scientists put rats on either a control diet or high fructose diet (HFD), with both groups receiving additional 300 mg/kg/day taurine via intra-peritoneal (i.p.) route for 35 days. While the decrease in body weight gain illustrated in figure 1 is relatively low, the overall effect of taurine on makers of the metabolic syndrome was significant: Fructose-fed rats showed significantly impaired glucose tolerance, impaired insulin sensitivity, hypertriglycer...

As avid visitor of the SuppVersity you may remember that taurine appears to exert beneficial effects on insulin resistance, body composition and overall health , but did you know that it is a vital nutrient for the formation of testosterone? In a recent study by Jang et.al. ( Jang. 2010 ) taurine has been shown to p rotect the rat testis from oxidant damage . Their study done on isolated rat leydig cells and living laboratory rats also revealed that the positive effect of taurine on testicular testosterone production is dose-dependend and bi-phasic, i.e. low concentrations of taurine (0.1–100 lg/ml) could stimulate testosterone secretion, whereas high concentration of taurine (400 lg/ml) could inhibit testosterone secretion. It is however relatively unlikely that levels >400lg/ml and thus negative effects will be achieved by orally administered doses of taurine . This hypothesis is validated by the results of the study (cf. Jang. 2010 Figure 5; below) which clearly illustrat...