"What people can tolerate varies widely based on age,
metabolism, activity level, body size and gender," says Dr.
Stephen Phinney, nutritional biochemist and an emeritus
professor of UC Davis. For healthy adults the number can be
higher, he says, while others will feel and function better if
they stay between 50 and 100 grams a day. "I've seen some people
get in trouble when they eat over 25 grams." If you're lean and
active, you can tolerate a higher carb intake than if you're fat
and sedentary, says Dr. Walter Willett, chairman of the
department of nutrition at the Harvard School of Public Health.
But genetic predisposition, he adds, will also play a role. Good
carb or bad? How to choose wisely Food scientists divide
carbohydrates into two categories: good and bad. A good carb is
one that doesn't raise your blood sugar quickly. (Some people
call these complex carbs.) Examples are whole grains, brown rice
and legumes. Bad, or simple, carbs trigger a fast rise in blood
sugar. Some examples are white bread, re