As a teenager, my grandfather lost a set of teeth due to the winter's cold, by sleeping in a cold barn, and he described it as a near-death experience. If anything, for many regions of the world, the weather getting hotter may be a relief for the poor that don't have heating in the winter.

We have zero reasons to be more depressed than prior generations. If we are depressed, don't you think the constant fear porn from mass-media has more to do with it?

PS: it's not just the carbs that are cheaper and more available. It's everything, including meat. Staples of any healthy vegan diet, like green peas, or lentils, weren't even available until ~1960, after industrial agriculture caught on. Never mind the availability of fresh fruits year-round. My grandparents basically lived on a diet of polenta, potatoes, milk, and eggs, as that's what they were able to grow.