In longevity research, there’s tons of animal studies looking at amino acid restriction- usually Met/Cys or some BCAA combo. In the fitness world, there’s almost exclusively aa-boosted products- high BCAA, high glutamine, etc. At the 2022 AGE conference, there were multiple presentations on the superiority of temporary Met restriction vs. chronic Met restriction. I’m really eager to try Met restriction, but it’s just not easy in combination with a high protein diet.

I analyzed available protein powders and got the following data. I’m going to try 1+ weeks of collagen (affordable from Bulk Supplements on amazon) with added Tryptophan and Glutamine and report changes in body composition, athletic performance, and subjective well-being.

What i see in the figure below is that collagen, gelatin, and beef bone broth powder are relatively low in Met/Cys and super high in Gly, which I have read is favorable for longevity. I love tryptophan (happy feelings!) and glutamine (anti-catabolic w/o mTOR activation + gut health) so I’m gonna add those in because I want more of them.