Raw fruit and vegetables
provide better mental health outcomes
University of Otago
That is the simple
message from University of Otago researchers who have discovered raw fruit and
vegetables may be better for your mental health than cooked, canned and
processed fruit and vegetables.
Dr Tamlin Conner,
Psychology Senior Lecturer and lead author, says public health campaigns have
historically focused on aspects of quantity for the consumption of fruit and
vegetables (such as 5+ a day).
However, the study,
just published in Frontiers in Psychology, found that for mental health in
particular, it may also be important to consider the way in which produce was
prepared and consumed.
"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," she says.
Dr Conner believes
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 were
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. 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," Dr
Conner says.
* 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.