Wednesday, February 9, 2011

A Natural Cure for Obesity and Insulin Resistance!? Promising Results from Animal Experiments with Bitter Melon Bioactives

In a very recent investigation, researchers from the Pennington Biomedical Research Center (Wang. 2011) found that high-fat diet fed mice gained less weight and had less compromised insulin response, if they received an (unfortunately) unspecified amount of an aquaeus extract from bitter melon:
Body weight, plasma glucose, insulin, leptin levels and HOMA-IR values were significantly lower in the BM-fed HFD group when compared to the HFD group. BM supplementation significantly increased IRS-2, IR β, PI 3K and GLUT4 protein abundance in skeletal muscle, as well as phosphorylation of IRS-1, Akt1 and Akt2 when compared with HFD (P<.05 and P<.01). BM also significantly reduced muscle lipid content in the HFD mice. BM extract greatly increased glucose uptake and enhanced insulin signaling in L6 myotubes. 
There is however two major caveat to these findings. Firstly, mice ain't a particularly good model for predictions concerning the effect of supplements that are added to a high fat diet. And secondly, even if we would see similar results in human beings, the most obvious conclusion one MUST (but obviously nobody does) draw from the results of this study is that without supplementation the low fat diet, i.e. the group of mice that consumed a diet that is appropriate to their genetic make-up, gained the least amount of weight, had the lowest leptin levels and the best insulin sensitivity.
Figure 1: Insulin levels of the mice on a low fat diet (LFD), a high fat diet (HFD) and a high fat diet supplemented with bitter melon extract (BM)
Does this tell you that you should revert to a low fat diet? No, at least not if you ain't a mouse. What it should tell you, however, is that revamping your diet, making correct food choices and eating according to what our bodies are made for is the key to health and long jeopardy - the "natural cure for obesity and insulin resistance", it's already out there. Don't even think about dietary supplements before you've got that in check...