New research has found that raw fruit and vegetables may be better for mental health than processed or cooked.
The University of Otago study found consumption of raw fruit and vegetables predicted improved levels of psychological well-being and lower levels of mental illness symptoms.
These mental health benefits were significantly reduced for cooked, canned and processed fruit and vegetables.
They studied 400 people from New Zealand and the US aged 18-25 as this age group typically had the lowest fruit and vegetable consumption and were at high risk of mental health disorders.
Lead author and psychology professor Dr Tamlin Conner says public health campaigns have historically focused on quantity of fruit and vegetables but the researchers suggest it is important to consider the way produce is prepared.
"Our research has highlighted that the consumption of fruit and vegetables in their 'unmodified' state is more strongly associated with better mental health compared to cooked/canned/processed fruit and vegetables."
Dr Conner said she believed this was because the cooking and processing of fruit and vegetables has the potential to diminish nutrient levels.
The top 10 raw foods related to better mental health were: carrots, bananas, apples, dark leafy greens such as spinach, grapefruit, lettuce, citrus fruits, fresh berries, cucumber, and kiwifruit.
"This research is increasingly vital as lifestyle approaches such as dietary change may provide an accessible, safe, and adjuvant approach to improving mental health," Dr Conner says.
The study was published in Frontiers in Psychology this week.
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