H.R.3503: To amend the Public Health Service Act to provide for a national program to conduct and support activities toward the goal of significantly reducing the number of cases of overweight and obesity among individuals in the United States.

Lifelong Improvements in Food and Exercise (LIFE) Act - Amends the Public Health Service Act to require the Secretary of Health and Human Services, acting through the Director of the Centers for Disease Control and Prevention (CDC), to carry out a national program to conduct and support activities regarding individuals who are overweight or obese in order to make progress toward the goal of significantly reducing obesity in the United States. Requires such activities to include: (1) training health professionals; (2) educating the public; and (3) developing and demonstrating intervention strategies for use at worksites and in community settings.