For starters, it's wrong to suggest that there's a direction or purpose to evolution[1]. The current shape of human life is no indication that we have 'progressed' from where we previously were, or where we will be in the future (as far as evo bio is concerned). As such, to suggest that we were 'supposed' to get smallpox because we did not evolve a natural immunity to it is not a statement that conforms to our understanding of evolution. Neither does it make sense that, because in the developed world, people have tended to become more sedentary, it is a desired end goal for humans to become 'lazier'. If that were the case, we should also be willing to argue that childlessness is the desirable state for living organisms, as the more education and wealth humans accumulate, the less likely they are to have children[2]. I don't fully follow your reasoning on exercise, but as it is intended to counteract the documented effects of overeating, I'm not sure it is a sound thesis to suggest it won't increase your lifespan.
1: http://www.talkorigins.org/faqs/evolphil/teleology.html 2: https://www.youtube.com/watch?v=BkSO9pOVpRM
there is a direction and purpose to evolution, it's: replicate or cease to exist.
I'm not taking sides here, I'm saying that you are being selective about what you choose to believe in a way that is not entirely supported by science. Yes you can selectively come up with science to support your beliefs, but what this article is about is how for many many years in modern times we all arrogantly believed the wrong science.
Your comment strikes me that you are not reading the news story about sugar as a cautionary tale against believing things that could quite well not be true.
I myself doubt that there is a magic diet that makes us live a long time, because living a long time is not something we evolved for; rather, we evolved to eat anything we could get our hands on because living thru times of shortage was more important than maybe having an allergy that made us gassier. 2nd order effects have a lot of trouble overcoming firsts.
And if you enjoy exercise, great! but if you don't enjoy it, remember that the hour you spend running will not lead to you living an hour longer, so you just shortened your overall enjoyable life, while you also increased your carbon footprint which is a socially selfish thing to do. See what I mean? these things just cannot be reduced to formulas for how we should live.