High-fruit diets can worsen depression

Forcing your children to have too much fruit during adolescence can have negative consequences as a diet high in fructose, a sugar found naturally in fruits, may exacerbate their depressive behaviours, new research shows.

The consumption of a diet high in fructose throughout adolescence can worsen depressive and anxiety-like behaviour and alter how the brain responds to stress, the findings showed.

"Our results offer new insights into the ways in which diet can alter brain health and may lead to important implications for adolescent nutrition and development," said lead author Constance Harrell of Emory University in Atlanta.

Fructose stimulates neural pathways that affect how the brain responds to stress, which can have important behavioural effects, including worsening symptoms of depression and anxiety, the researchers found.

Such effects are of particular concern during the teen years, which is a critical time for the development of the brain's stress response.

For the study, the researchers gave both adolescent and adult rats either a standard or a high-fructose diet.

After 10 weeks, the adolescent rats on the high-fructose diet had a different stress hormone response to an acute stressor, which was consistent with their depressed-like behaviour.

A genetic pathway in the brain that plays a key role in regulating the way the brain responds to stress was also altered.

The findings were presented Neuroscience 2014, the annual meeting of the Society for Neuroscience at Washington DC.