Young People Practicing Unhealthy Habits They show greatest increase in smoking, obesity and poor eating, study says    HealthDayNews -- Smoking, obesity and poor eating habits increased among young people in the United States in the 1990s, a trend that may lead to higher future rates of cancer, heart disease, diabetes and lung disease as that generation ages.    That warning comes from a study in the September/October issue of the American Journal of Health Promotion...