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Leucine and BCAAs (branched chain amino acids)
BCAAs can be obtained through the internet. Please see related topics that provide supporting evidence on the high protein diet, and a recent article A high-protein diet induces sustained reductions in appetite.
An article May 12, 2006 indicates that a key to appetite suppression and weight loss may be getting enough of an amino acid found in protein called leucine. Just as carbohydrates are polysaccharides made of many sugar molecules, proteins are polyamino acids, made of about 22 different amino acids. In the article cited below, the authors report that neurons in the brain directly signal satiety (being full, not hungry) and to burn extra calories.
Regulating Energy Balance: The Substrate Strikes Back, Jeffrey S. Flier, Science 12 May 2006: 861-864.
The main story, Hypothalamic mTOR Signaling Regulates Food Intake, by Daniela Cota et al, Science 12 May 2006: 927-930, states
Here is some background on the amino acid leucine. It is a member of the branched-chain amino acid family, along with valine and isoleucine. The three branched-chain amino acids constitute approximately 70 percent of the amino acids in the body proteins. As such, their value in the formation and maintenance of structural and functional integrity in humans is unmeasured.
During times of starvation, stress, infection, or recovery from trauma, the body mobilizes leucine as a source for gluconeogenesis (the synthesis of blood sugar in the liver) to aid in the healing process. It has recently been suggested that leucine may have beneficial therapeutic effects on the prevention of protein wasting, as it occurs during starvation, semi-starvation, trauma, or recovery after surgery. Insulin deficiency is known to result in poor utilization of leucine; therefore, individuals who suffer from glucose intolerance may require higher levels of leucine intake. It has also been recently suggested that leucine has anabolic effects, thereby preventing muscle protein breakdown and stimulating muscle protein synthesis. Therapeutic use of leucine occurs at doses between 500 and 1,000 mg per day.
Foods high in leucine include:
Here's another article suggesting leucine may have benefits:
Dec. 1, 2004 – Eggs, which not long ago were taking a beating in nutrition circles, are touted today in the Journal of the American College of Nutrition as helping older women in weight loss and reducing the risk of cataract and age-related macular degeneration (AMD).
And here is another story from webmd dating back to February, 2003, titled "Protein diet may prompt Weight Loss" in the Journal of Nutrition, also highlighting the role of leucine. "Though all the women lost about 16 pounds each, those in the higher-protein group lost more body fat and retained more lean muscle than those the high-carb group. "However, when we did a follow-up four months later, we found the higher-protein group continued to lose weight while the high-carb group had plateaued and lost no additional weight," says Layman. The researchers also found that the higher-protein group had lower blood sugar levels, making them less prone to type 2 diabetes."
Leucine references - here are many articles you can read documenting the beneficial effects of leucine
1. Garlick, P.J. The role of leucine in the regulation of protein metabolism. J Nutr, 2005. 135(6 Suppl): p. 1553S–6S.