There are aboriginal people with a diet low in protein like New Guinea highlanders who subsides mostly on sweet potato and other starchy vegetables. Their prot

There are aboriginal people with a diet low in protein like New Guinea highlanders who subsides mostly on sweet potato and other starchy vegetables. Their protein intake is like 35-40 grams/day, https://pubmed.ncbi.nlm.nih.gov/7328441/ https://pubmed.ncbi.nlm.nih.gov/7328441/ Yet they are not known for a particularly long life span. One can argue as aboriginal people they do not have access to modern medicine and most people die from preventable diseases. Yet it does allow to doubt that just by protein restrictions one can noticeably prolong life in humans. Also their dies is low in fats, so again, this makes one skeptical towards claims that low-fat diet prolongs life.