Our life expectancy, as you mean it, has not significantly increased in a very long time. Overall life expectancy appears to have increased because it's generally expressed as from birth, meaning that small reductions in infant mortality have large effects.
The life expectancy of an 18 year old now is barely less than it was before even antibiotics. The last really large jump came with the advent of indoor plumbing.
If you want more about the effects of diet on health, read In Defense of Food by Michael Pollan.
I concede nothing in my core argument --- I read through this writer's previous work at the Turbo-Conservative Hoover Institution, and I'm convinced she's a culture warrior, and that the subtext of this article is that if we fail to oversee the compliance of our neighbors sex lives to her standards, we'll all die of Super AIDS --- but the bit about life expectancy vs. infant mortality was new to me, and thanks.
The life expectancy of an 18 year old now is barely less than it was before even antibiotics. The last really large jump came with the advent of indoor plumbing.
If you want more about the effects of diet on health, read In Defense of Food by Michael Pollan.