** Would living more than 100 years be an advantage for the human species? ** I don't think so. First of all, recall that the median lifespan in the late Paleolithic was about 35 years (see Ward Nicholson's Health & Beyond interview), that is to say, half of the population died before reaching 35 years old, and humans have very well survived! Also, the population of the !Kung Bushmen in 1964 was 60+ years: 10% 15-59 yrs: 60% 0-14 yrs: 30% which means that, once they are adults, they have good chances of reaching 60 years old, but don't live much longer. But even with that "short" longevity, they know virtually everything about their environment they need. Remark: with any diet, you will find centenarians. Some people certainly have such genetic advantages that they would survive with the SADdest nutrition. What is more interesting is looking at averages (conditions of medical care and hygiene being equal). ** Is it reasonable to think that the natural lifespan of humans is 1000 years ? ** This seems such a ridiculous question, but let's address anyway. There have been many comparisons of lifespans between different species, based on the number of heartbeats, of breaths, of the metabolism rate, surface, body weight. None of these theories has been conclusive, but they *very* roughly (with factors 2 or 3 errors) give an idea of the lifespan of a given species. And with whatever method you determine human lifespan, it's no more than about 100 years. More recently, scientists have explained natural aging in terms of shortening of "telomeres". See my post http://maelstrom.stjohns.edu/CGI/wa.exe?A1=ind9708&L=raw-food&O=T&H=0&D=0&T=1#12 and the subsequent discussion. [They talked about that informally on CBS this morning, I think that scientists can treat cells with telomerase], and the number of possible cell divisions (50 for human cells) is well correlated with telomere length at birth. Other remarks: no mammal lives more than approximately 100 years. Giant tortoises live 180 years. Best wishes, Jean-Louis [log in to unmask]