Reply To: How I eat a high glycine, high protein, and lower methionine diet

“When rats were fed a diet completely lacking tryptophan for a short period, or a diet containing only one fourth of the “normal” amount for a more prolonged period, the results were surprising: They kept the ability to reproduce up to the age of 36 months (versus 17 months for the rats on the usual diet), and both their average longevity and their maximum longevity increased significantly. They looked and acted like younger rats. (A methionine-poor diet also has dramatic longevity-increasing effects.)” -Ray Peat