>calorie restriction I've read that restricting the amino acid methionine produces results very similar to calorie restriction: Life-span extension in mice by preweaning food restriction and by methionine restriction in middle age. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2691799/?tool=pubmed Also: http://www.ncbi.nlm.nih.gov/pubmed/20041736 Peter