Higher than predicted resting energy expenditure and lower physical activity in healthy underweight Chinese adults.

Contrary to popular opinion that lean individuals "eat what they want" and exercise more, Hu et al. study a cohort of healthy underweight volunteers and reveal them to have reduced physical activity relative to normal BMI controls and lower food intake. This cohort is also shown to have higher than expected resting energy expenditure, which is associated with elevations in thyroid hormones.