Remain positive to become healthier adults says a Northwestern University study. Focusing on the terrible teenage years can be a good way to combat stress in later life.

Research found that all troubles associated with mid-life health risks - diabetes, hypertension, lung disease - could be avoided by reducing the risk of negative behaviour associated with binge drinking, smoking and drugs including eating unhealthy foods.

"Our study shows that promoting and nurturing positive well-being during the teenage years may be a promising way to improve long-term health," said Lindsay Till Hoyt, first author of the study and a fifth-year doctoral student in human development and social policy at Northwestern.

"Positive well-being is more than just the absence of depression; the influence of a teenager's positive well-being on long-term good health is present even after accounting for the negative health effects of experiencing depressive symptoms in adolescence," added K. Adam, co-author of the study.

The study, one of the first to focus on the effect positive psychological characteristics in adolescence, is published in the July 2011 issue of the Journal of Adolescent Health.

Results come from 10,147 young people studied since 1994.