Data from: Parsing the life-shortening effects of dietary protein: effects of individual amino acids

High-protein diets shorten lifespan in many organisms. Is it because
protein digestion is energetically costly or because the final products
(the amino acids) are harmful? To answer this question while circumventing
the life-history trade-off between reproduction and longevity, we fed
sterile ant workers on diets based on whole proteins or free amino acids.
We found that (i) free amino acids shortened lifespan even more than
proteins; (ii) the higher the amino acid-to-carbohydrate ratio, the
shorter ants lived and the lower their lipid reserves; (iii) for the same
amino acid-to-carbohydrate ratio, ants eating free amino acids had more
lipid reserves than those eating whole proteins; and (iv) on whole protein
diets, ants seem to regulate food intake by prioritizing sugar, while on
free amino acid diets, they seem to prioritize amino acids. To test the
effect of the amino acid profile, we tested diets containing proportions
of each amino acid that matched the ant's exome; surprisingly,
longevity was unaffected by this change. We further tested diets with all
amino acids under-represented except one, finding that methionine, serine,
threonine and phenylalanine are especially harmful. All together, our
results show certain amino acids are key elements behind the high-protein
diet reduction in lifespan.