Could people one day evolve to eat rich food while remaining perfectly slim and svelte?
This may not be so wild a fantasy. It is becoming clear that the human genome does respond to changes in diet, even though it takes many generations to do so.
Researchers studying the enzyme that converts starch to simple sugars like glucose have found that people living in countries with a high-starch diet produce considerably more of the enzyme than people who eat a low-starch diet.