Raw fruit and vegetables may be better for your mental health than cooked, canned and processed fruit and vegetables.
University of Otago researchers have discovered raw fruit and vegetables provide better mental health outcomes, but the trick is in the way they are prepared and consumed.
Psychology senior lecturer and lead author Dr Tamlin Conner says public health campaigns usually focus on aspects of quantity for the consumption of fruit and vegetables – such as the 5+ a day campaigns – but for mental health, raw is best. “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,” Conner says. “This could be because the cooking and processing of fruit and vegetables has the potential to diminish nutrient levels. This likely limits the delivery of nutrients that are essential for optimal emotional functioning.”
For the study, more than 400 young adults from New Zealand and the United States aged 18 to 25 were surveyed. This age group was chosen as young adults typically have the lowest fruit and vegetable consumption of all age groups and are at high risk for mental health disorders.
The group’s typical consumption of raw versus cooked and processed fruits and vegetables was assessed, alongside their negative and positive mental health, and lifestyle and demographic variables that could affect the association between fruit and vegetable intake and mental health (such as exercise, sleep, unhealthy diet, chronic health conditions, socioeconomic status, ethnicity and gender).
“Controlling for the covariates, raw fruit and vegetable consumption predicted lower levels of mental illness symptomology, such as depression, and improved levels of psychological wellbeing including positive mood, life satisfaction and flourishing,” she says. “These mental health benefits were significantly reduced for cooked, canned and processed fruits and vegetables. This research is increasingly vital as lifestyle approaches such as dietary change may provide an accessible, safe and adjuvant approach to improving mental health.”
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.