Eating 1 gram of animal protein per pound of body weight extends your life by preserving muscle and brain, but you need to add 15 grams of glycine daily to balance the methionine in that protein. The ratio matters more than the protein amount alone.
I believe that the 1 gram of animal protein per pound of body weight is the diet that is going to give you the most longevity because it's going to keep you from losing muscle. It also is going to keep you from losing brain mass. But, and this is a big but, it only works if you're supplementing either collagen or glycine, because it's not the presence of methionine that's the issue. It's the ratio of methionine to glycine. And glycine is a beneficial amino acid. So if you take 15 grams of glycine a day on top of one gram per pound of body weight, you're going to have an optimal longevity situation.
