Mental health disorders affect nearly 1.2 billion people globally, study finds

Nearly 1.2 billion people worldwide were living with mental health disorders in 2023, marking a 95.5% increase since 1990, according to a new global study reported by CNN citing research published in The Lancet.

The study is based on the 2023 Global Burden of Diseases, Injuries and Risk Factors (GBD) analysis led by the Institute for Health Metrics and Evaluation at the University of Washington. It examined mental health trends across 204 countries and territories and assessed 12 different mental health disorders over time.

Researchers found that anxiety and depression remain the most common mental health conditions globally. These are followed by a residual category of personality disorders not accompanied by other mental health conditions or substance use disorders. The authors warned that global trends suggest the world may be entering "an even more concerning phase of worsening mental disorder burden".

According to the findings, anxiety disorders increased by 158% between 1990 and 2023, while depression rose by 131% over the same period. Although less common overall, anorexia, bulimia and schizophrenia were also recorded in significant numbers, with millions of cases reported globally. Autism spectrum disorder, attention deficit hyperactivity disorder (ADHD), conduct disorder, personality disorders and intellectual disability were found to be more prevalent among males, while most other disorders were more common among females.

The study also highlighted how the Covid-19 pandemic influenced global mental health trends. It found that rates of anxiety, depression and several related disorders were already increasing before the pandemic, but the crisis further intensified the situation. Depression levels increased during the pandemic and have not returned to pre-pandemic levels, while anxiety peaked and remained high through 2023.

Lead author Dr Damian Santomauro told CNN that he was "honestly shocked at the magnitude" of the findings. He said multiple factors are contributing to the rise, although it is difficult to separate their individual effects. He also stressed that addressing the global mental health burden would require coordinated international action and stronger leadership.

The research also revealed a major shift in age distribution. Mental disorders are now most prevalent among people aged 15 to 39, with the highest burden recorded in the 15–19 age group. This marks the first time in the history of the GBD study that teenagers have shown the highest level of mental health burden, replacing the previously observed peak among middle-aged populations.

Experts not involved in the study pointed to several possible reasons behind the rise in reported cases. These include improved diagnosis, reduced stigma around mental illness, population growth and longer life expectancy. Experts also noted that people are now more willing to seek help compared to previous decades, which may contribute to higher recorded prevalence.

At the same time, researchers emphasised the role of broader social, economic and environmental pressures. These include economic instability, trauma, inadequate or unaffordable healthcare, political conflict and warfare, food insecurity, discrimination, declining social connections, environmental threats and intimate partner violence. Young people, in particular, are believed to be disproportionately affected by these combined stressors.

Dr Paul Bolton, a senior scientist at the Johns Hopkins Bloomberg School of Public Health, told CNN that underreporting remains a challenge in mental health data. However, he added that the estimates are "the best we have" and are likely the closest reflection of global reality currently available.

Despite rising awareness of mental health issues, the study warned that the expansion of mental health services has not kept pace with growing demand. The authors described this gap as a major global concern and said responding to mental health needs, especially among vulnerable populations, should be considered an obligation rather than an option.

Experts also suggested ways to support mental wellbeing, including seeking professional help such as therapy or medication when necessary. They also highlighted lifestyle factors that can help improve mental health outcomes, including maintaining good sleep patterns, regular physical activity, balanced nutrition, social connection, hobbies and maintaining a healthy work-life balance where possible.

The report also referenced international support resources for people experiencing mental health difficulties. These include Mental Health America and the National Alliance for Eating Disorders in the United States, Mind in the United Kingdom, the International Association for Suicide Prevention and Befrienders Worldwide for global support, and the Butterfly Foundation in Australia, which offers helplines and online support services.