You Are What You Just Ate

The new science of nutrition promises customized dietary recommendations designed to keep you healthy and to ward off disease.

- By Adam Piore

I knew a guy in college who could consume heaping bowls of ice cream without any discernable effect on his six-pack abs. I've been wondering ever since why my body doesn't respond that way to my favorite dessertor, for that matter, if I'll ever find one that I won't regret the next day when I step on the scale. Recent advances in nutrition science now are edging closer to delivering on my dream of dessert with impunity and a lot of other health benefits, besides.

It's long been obvious, to scientists and lay people alike, that each person responds differently to a given food or diet regimen. For years, scientists have tried to figure out how to accommodate these idiosyncrasies in a way that improves health and avoids common ailments such as heart disease, obesity and diabetes-and, for better or worse, helps people lose weight.

After years of trying to find genes that might account for individual differences, scientists have come to realize that genes alone cannot explain the human body's relationship to food in all its complexity. Diet and health involve genes and many other factors besides, including sleep, exercise, stress and other lifestyle matters. One of the biggest factors perhaps the biggest-is the community of trillions of individual microorganisms that live in each person's gut, called the microbiome.

This news is good because, while you can't change your genes, you can cultivate healthy gut bacteria, change the timing of meals and adjust diet and lifestyle factors to optimize metabolic health.