One more serve of fruit linked to lower depression and anxiety risk in teenagers

A study of more than 6,500 Australian adolescents found that an extra daily serve of fruit was associated with lower risks of depressive and anxiety symptoms, while sugary drinks showed the opposite pattern.

A new University of Sydney study suggests that even modest changes in diet may be linked to better mental health in teenagers, with fruit intake standing out as a possible protective factor. Researchers followed more than 6,500 adolescents from 71 secondary schools across New South Wales, Queensland and Western Australia, tracking their eating habits and mental health from the start of high school through to Year 10. The work adds to a growing body of evidence that everyday food choices may matter not only for physical health, but also for emotional wellbeing.

According to the study, eating one additional serve of fruit a day was associated with a 13% lower risk of depressive symptoms and a 7% lower risk of anxiety symptoms. The researchers also found that higher consumption of sugary drinks, including soft drinks, cordials and sports drinks, was linked with a greater risk of depression and anxiety. That association was especially pronounced among boys, particularly for anxiety.

Lily Davidson, the study’s lead author from the University of Sydney’s Matilda Centre for Research in Mental Health and Substance Use, said the findings should not be read as a simple cause-and-effect claim. “We’re not saying eating an apple will prevent depression, or that having a soft drink will cause anxiety – mental health is far more complex than that,” she said. But, Davidson added, diet is one part of life that can be changed, which makes it a useful target for prevention.

The study differs from some earlier research because it did not include adolescents who were already meeting the criteria for depression or anxiety at the outset. That design, Davidson said, helped the team examine whether diet preceded later symptoms rather than simply reflecting them. Similar findings have appeared in other research, including a 2024 University of Sydney report on small lifestyle changes and adolescent mental health, as well as earlier studies and reviews that linked higher fruit and vegetable intake with lower levels of depression, anxiety and psychological distress in young people.

Senior author Katrina Champion said the results underline the importance of prevention, not just treatment, in youth mental health. She said making healthy food more affordable and accessible for families is part of the solution, alongside support from schools and governments. The study’s findings fit with wider public health advice that encourages teenagers to eat more fruit and fewer sugary drinks, while recognising that mental health is shaped by many factors beyond diet alone.