This scientific uncertainty is not overly surprising given that humans eat so many different foods. And interpretation is influenced by the individual’s point of view, which can become thoroughly entangled with the science. Nutrition research is so difficult to conduct that it seldom produces unambiguous results. The noted cardiologist Ancel Keys (who died in 2004 at the age of 100) and his wife, Margaret, suggested similar principles for preventing coronary heart disease nearly 50 years ago.īut I can see why dietary advice seems like a moving target. Ironically, this advice has not changed in years. If you follow these precepts, other aspects of the diet matter much less. Soft drinks are the prototypical junk food they contain sweeteners but few or no nutrients. Avoiding junk food means to shun “foods of minimal nutritional value”-highly processed sweets and snacks laden with salt, sugars and artificial additives. Eating fruits, vegetables and whole grains provides nutrients unavailable from other foods. “Move more” refers to the need to balance calorie intake with physical activity. “Eat less” means consume fewer calories, which translates into eating smaller portions and steering clear of frequent between-meal snacks. Nevertheless, basic dietary principles are not in dispute: eat less move more eat fruits, vegetables and whole grains and avoid too much junk food.

Yes, nutrition advice seems endlessly mired in scientific argument, the self-interest of food companies and compromises by government regulators. Whose information, people ask, can we trust? I’m tempted to say, “Mine, of course,” but I understand the problem. As a nutrition professor, I am constantly asked why nutrition advice seems to change so much and why experts so often disagree.

Marion nestle food