A UC Davis Health study published in Psychological Medicine suggests that sleep may play a more significant role than screen time, exercise, or diet in helping adolescents succeed academically and maintain healthy friendships, particularly for those experiencing anxiety, depression, or other mental health challenges. The findings were announced on Aug. 4.
Researchers examined the influence of four lifestyle factors—sleep quality, screen time, physical activity, and diet—on the relationship between mental health symptoms and academic and social functioning among children ages 10 to 13. They found that sleep was the strongest factor associated with better grades and fewer social problems. Screen time ranked as the second strongest factor.
"This finding surprised us," said Jason Smucny, the study's first author and a computational neuroscientist in the Department of Psychiatry and Behavioral Sciences. "We expected sleep to be important, but we didn't expect it to stand out so clearly above other lifestyle factors, particularly screen time."
The study notes that adolescence is a critical developmental period when mental health concerns often emerge globally; about one in seven adolescents experience a mental disorder such as depression or anxiety. "Parents, educators and clinicians understandably focus on symptoms like anxiety and depression," said senior author Tara Niendam, professor of psychiatry and executive director of the UC Davis Early Psychosis Programs. "But what often matters most to young people and their families is how those symptoms affect everyday life — how they perform in school, connect with friends and navigate daily challenges. This study suggests that sleep may be one pathway linking mental health to those real-world outcomes."
Using data from the Adolescent Brain Cognitive Development Study (ABCD), researchers found that healthy lifestyle habits explained a substantial portion of the relationship between mental health symptoms and school performance. Sleep accounted for 18.5% of the association with depression-related lower grades, 36.3% with anxiety-related lower grades, and 8.3% with psychotic-like disturbances; screen time accounted for smaller percentages.
The researchers emphasized that while healthy lifestyle habits are not substitutes for professional mental health care, their findings suggest sleep may be an important target for supporting young people facing mental health symptoms, "What is encouraging is that sleep is something parents and families can address," Niendam said. "While it won't solve every mental health challenge, healthy sleep routines are a practical way to support a child's emotional well-being and day-to-day functioning."
