For 2 million years of our evolution, we ate much less
carbohydrate than we do now, and no refined or processed
carbohydrates, and therefore, our systems are simply not designed to
handle the big swings in blood sugar
levels caused by the Western diet, which is very
high in
carbohydrates of all kinds.
People who have an already damaged metabolism from eating
high levels of added sugar (who are also probably more sedentary) can not
handle the same amount of
carbohydrates as someone with a healthier metabolism.