The New Year signals a clean slate (and a clean plate!). The good news: Implementing even small everyday diet and exercise changes can lead to a long-term difference, says Lee Goldman, MD, executive vice president and dean of the faculties of health sciences and medicine at Columbia University Medical Center. When it comes to exercise, “the simple message is to stay active,” he says. Focus on building activity into your daily routine, he adds, whether it’s going to the gym, walking several extra blocks rather than driving, or taking the stairs instead of the elevator. Dr. Goldman also cautions against the common mistake of celebrating your new exercise routine with heartier meals. “Don’t overestimate how many calories you burn with exercise and reward yourself by eating just as many—or more,” he stresses.