The Main Public Health Problem of Population in the Future: Aging Conditions or Adolescent and Youth Conditions

Nowadays, most policy makers state that the main public health problem of many populations is aging and related consequences and therefore chronic diseases among elder people will be the most important problems of future (1-5), although it has been confirmed that the origin of many elderly diseases returns to the early life conditions (6, 7). Furthermore, many developing 
countries are experiencing a huge adolescents and youth population which their problems have often been neglected due to aging of their populations. In fact, health professionals are involved in the health of aging population as well as health of adolescents and youth because 
of their substantial effects on most of the morbidities in aged community.
Fortunately, many morbidities and mortalities of adolescents and youth could be prevented; however, it is unknown that how, when, and in whom, these conditions would develop in early adolescence and youth. There are many different problems among adolescents and youths 
including mental health issues and their potential relations with risky behaviors (with prevalence of 15%), risky sexual behavior, sexually transmitted diseases (STD), early sexual experience as well as sexual abuse and the increased use of alcohol and marijuana at younger ages 
(8). Unhealthy lifestyle could indeed be considered as the most important issue among adolescents and youths. In fact, unsafe lifestyles in young generation will have a costly consequence for the health services in the future. For instance, Hooshmand and colleagues studied on 4412 adolescents (49% female) who were followed up from grade nine to 12 on their depressive symptoms and six healthrisk behaviors (alcohol use, amount of alcohol consumed per drinking episode, cigarette smoking, marijuana use, hard drug use, and delinquency) (9). In another study, Garrusi and colleagues performed a study to explore the 
way that Iranian University students live (10). They found that some students, particularly those who were studying medicine, were not enjoying a healthy lifestyle, with better situation of female students than males.
It remains a big question to be answered: "What should we do now?" In one hand, the world population is going old with their own conditions; on the other hand, many (developing) countries have huge adolescent and young population with special needs and attention. Due to the lack of enough financial support for research and delivering services to both groups, what will be the decision of national decision makers about making a balance in giving services to these two important age groups? Do we know about the health services inequality among these 
two groups? Tomorrow would be too late to think about the ways of improving healthy lifestyle among current young people and future elderly population. Today is the time for action