A new study suggests food changes mood and that eating fruit and vegetables each day helps keep the blues away.
Eating more fruit and vegetables may make young people calmer, happier and more energetic in their daily life, the University of Otago research indicates. Otago psychology department researcher Dr Tamlin Conner, and Dr Caroline Horwath and Bonnie White, both of the Otago human nutrition department, explored the relationship between day-to-day emotions and eating.
The study, which analysed the consumption of food, and of a wide range of fruit and of vegetables, including carrots, was published in the British Journal of Health Psychology yesterday.
The results showed a strong day-to-day relationship between more positive mood and higher fruit and vegetable consumption.
''On days when people ate more fruits and vegetables, they reported feeling calmer, happier and more energetic than they normally did,'' Dr Conner said.
She was ''excited about the findings'', which added to a ''really interesting and growing research area'', exploring links between food consumption and mood.
A total of 281 young adults, with a mean age of 20, completed an internet-based daily food diary for 21 consecutive days, rating how they felt and indicating what they had eaten that day. They were asked to report the number of servings eaten of fruit - excluding fruit juice and dried fruit - vegetables, excluding juices, and of several kinds of unhealthy foods, such as biscuits or cookies, potato chips and cakes or muffins.
Later analysis showed young people would need to eat about ''seven or eight total servings of fruits and vegetables per day to notice a meaningful positive change''. One serving of fruit or vegetables was about the ''size that could fit in your palm, or half a cup''. Her co-author Ms White suggested this could be done ''by making half your plate at each meal vegetables, and snacking on whole fruit, like apples'', Dr Conner said. She emphasised she was not suggesting dietary change as an alternative treatment for depression.
But there was ''growing recognition'' that eating more fruit and vegetables provided benefits for both physical and mental health.
Choosing to each more fruit and vegetables was ''one small thing that we can do''.
