Recently, she presented her fresh ideas on food at the Bi-Annual Research Day held at the West Virginia School of Osteopathic Medicine, which focused on “Basic Science and its Transformation of Medicine.”

The key to addressing obesity, says Lieberman, is to better understand our ancestral roots and then use that information to interpret our present-day health behaviors and attitudes about food.¬†Currently, 66 percent of all Americans are overweight–Lieberman’s work suggests this is because the way we eat is designed for an entirely different way of life.

So, what’s changed? For starters, food is plentiful and convenient in today’s world but we still behave like every meal is our last.

“Food was often scarce for our ancestors, so during the times that it was plentiful we had a tendency to eat as much as we could,” Lieberman said. “We still act like our ancestors, even though our lives are nothing like they were then. These residual behaviors are an underlying cause of obesity.”

She suggests that we all watch our portion sizes. “Food and drink portions are usually too big; we should use smaller plates and cups,” she said. ‘When you eat out, share your meal with someone–or take a portion home for leftovers.”