A new study from the World Health Organization finds that psychiatric disorders are the leading cause of disability among adolescents and young adults. The study is the first to provide a global picture of the health of people in this age group.
Young people from 10-24 should be among the healthiest. They're old enough to escape the danger from childhood diseases, and too young to be ravaged by cancer, heart disease, and other conditions that afflict the old.
But a new study upends that view, looking past death rates to a measure called Disability Adjusted Life Years (DALY), that takes into account not just death but illness.
Using a database called the Global Burden of Disease, researchers found mental health issues accounted for almost half the illness they charted in the 10-24 year old age group.
"In terms of the top 10 causes of burden of disease in this age group, five of them are mental disorders such as depression, schizophrenia, bipolar disorder, alcohol abuse, and suicide and self-harm," said Dr. George Patton of Australia's University of Melbourne, one of the senior co-authors of the new study.
Since this is the first time a study like this has been done, it's not really possible to talk about trends, but Patton noted some regional patterns. In Africa, for example, infectious diseases remain a serious problem.
"So, HIV, TB, and malaria are prominent causes of both mortality and morbidity - that is, disability - together with this being the region where maternal mortality and the consequences of childbirth in terms of disability are much greater than in other parts of the world."
By contrast, in the Western Pacific, dominated by China, the picture is similar to high-income countries, where disability is dominated by mental disorders and injuries, notably traffic accidents.
In addition to the diseases and conditions that contribute to the poor health of young people, Patton says habits picked up in youth - smoking and alcohol use, obesity, and unsafe sex, for example - can lead to illness and early death decades later.
"These emerge in these years, and these cause a huge burden of disease later in life. Interventions are going to be so much more effective if we're intervening early on," he said.