Most of us know that to be healthy, we need to eat well and exercise.
But focusing on just those two things may not be enough, according to a theory investigated (and experienced) by journalist and anthropologist Scott Carney in his recent book “What Doesn’t Kill Us: How Freezing Water, Extreme Altitude, and Environmental Conditioning Will Renew Our Lost Evolutionary Strength.”
This theory suggests that along with diet and exercise, our bodies might need environmental stress — like exposure to cold and hot temperatures — if we’re to reach our full potential. Humans had no air conditioning or heating to help protect us from extreme conditions for most of our existence, after all.
The logic behind this idea is similar to explanations for why we need to eat healthy food and work out. Nature is brutal, and we have evolved to survive in a harsh world, but now modern technology shields us from those physical challenges.
We’re built to move and run; being sedentary leads to higher incidences of heart disease, cancer, and diabetes — many of the most common causes of death in the modern world.
And our bodies thrive when we eat natural foods similar to what we’d be able to grow and find in the wild; they experience negative consequences when we consume too many processed materials. We seek out sugar and fat because of their high caloric content, but those foods have become so accessible that we’re eating in more unhealthy ways.
The idea behind environmental conditioning is the same.