Various amino acids, which are the elemental forms of protein, are touted to increase the release of human growth hormone (GH). Among these aminos, arginine is considered the most potent in this regard. On the other hand, the use of supplemental arginine for boosting GH release remains controversial. One reason for this is that the studies that showed an effect of arginine in promoting GH release usually involved an intravenous administration of large doses of arginine. This is significant because ingesting too much of an oral dose of arginine can lead to rapid nausea. In addition, an enzyme in the liver tends to degrade larger doses of arginine. But what about whole protein foods for boosting GH release? A new study tested various whole protein sources to see what effect they would have on GH release. An earlier study showed that soy protein, often considered an inferior protein source for bodybuilding purposes, significantly boosted GH release. The effect was linked to the amino acid content of soy, particularly arginine and lysine. In the new study, soy was compared with gelatin; alpha lactalbumin, a major whey protein; and whole milk protein. All the proteins were provided in the same dose: 0.6 grams of protein per kilogram of bodyweight. These doses were ingested by eight healthy women, age range, 19 to 26.
Care to guess which protein source promoted the greatest release of GH? Most people would probably point to the milk protein sources as being superior in this regard. But they would be wrong. In fact, the cheap gelatin protein promoted the greatest GH release. It turns out that gelatin, of all the proteins tested in this study, had the highest arginine content. Before you run out and buy a gelatin supplement, which is often sold under the name "hydrolyzed protein," consider the fact that gelatin is a poor quality protein, being nearly devoid of the essential amino acid, tryptophane.
Van Vught AJ, et al. The effects of dietary protein on the somatotropic axis: a comparison of soy, gelatin, a-lactalbumin, and milk. Eur J Clin Nutr 2010: in press.
©,2013 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited.
