John Bryson writes "Eating less of one amino acid might lengthen your life. There have been lots of previous studies showing that many species live long on highly restricted calories, but a lot of this benefit may be possible by only restricting one amino acid. Amino acids that have shown this have been tryptophan and methionine. A recent study, published online December 2 in Nature, a highly respected journal, may help explain some of the health benefits of restricted-calorie diets. Grandison, R.C., Piper, M.D.W., and Partridge, L. 2009. Amino-acid imbalance explains extension of lifespan by dietary restriction in Drosophila. Nature, published online Dec. 2. doi:10.1038/nature08619"
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