Quality Matters Most

An average adult gains one pound per year. Small changes in diet, consumption of beverages, physical activity, watching TV, and sleep duration were most strongly linked to long-term weight gain. The idea of 'eat less and exercise more' may be too simplistic a weight-loss strategy, as it is the quality of food that matters most and making a handful of small, targeted changes is likely to be most effective.
New England Journal of Medicine, June 2011