Monday, August 9, 2010

Naringenin Improves Insulin Signaling and Sensitivity

"Eat Grapefruit and lean out!" Using google, you will find similar sentences all over the web. Yet, although it sounds too good to be true - as it is often the case - there is some truth at the bottom of this rumor. A few weeks ago scientists from the Annamalai University in India published a paper (Kannappan. 2010) that established a positive effect of naringenin, a bioflavonoid, from grapefruit an other citrus fruits, on insulin signaling and sensitivity.
Fig.1: Oral glucose tolerance test curves of experimental animals.
Values are mean ± SD (n = 6). CON control rats, FRU fructose-fed
rats, FRU + NAR fructose-fed rats treated with naringenin (50 mg/kg
b.w.), CON + NAR control rats treated with naringenin (50 mg/kg
b.w.). (Kannappan. 2010)
It is easy to see from Fig. 1 that the supplementation of 50mg/kg naringenin prevented the rise in blood glucose and restored insulin sensitivity in high-fructose fed rats.
Not only diabetics may benefit from these findings, bodybuilders and fitness enthusiasts who are convinced that the "carbohydrate mast" (i.e. consuming large amounts of carbs post workouts) is beneficial or even necessary for appropriate muscle gain may well use some naringenine to keep healthy blood sugar levels, prevent insulin resistence and increase glucose uptake in the post-workout "anabolic window".