University of Warwick
University of Warwick research indicates that eating more fruit
and vegetables can substantially increase people's later happiness levels.
To be published shortly in the American Journal of
Public Health, the study is one of the first major scientific attempts to
explore psychological well-being beyond the traditional finding that fruit and
vegetables can reduce risk of cancer and heart attacks.
Happiness benefits were detected for each extra daily portion of
fruit and vegetables up to 8 portions per day.
The researchers concluded that people who changed from almost no
fruit and veg to eight portions of fruit and veg a day would experience an
increase in life satisfaction equivalent to moving from unemployment to
employment.
The well-being improvements occurred within 24 months.
Cancer
The study followed more than 12,000 randomly selected people.
These subjects kept food diaries and had their psychological well-being
measured.
The authors found large positive psychological benefits within two
years of an improved diet.
The work is a collaboration between the University of Warwick,
England and the University of Queensland, Australia.
The researchers found that happiness increased incrementally for
each extra daily portion of fruit and vegetables up to eight portions per day.
The study involved an examination of longitudinal food diaries
of 12,385 randomly sampled Australian adults over 2007, 2009, and 2013 in the
Household, Income, and Labour Dynamics in Australia Survey.
The authors adjusted the effects on incident changes in
happiness and life satisfaction for people's changing incomes and personal
circumstances.
Western diet
The study has policy implications, particularly in the developed
world where the typical citizen eats an unhealthy diet. The findings could be
used by health professionals to persuade people to consume more fruits and
vegetables.
Dr Redzo Mujcic, research fellow at the University of
Queensland, said: "Perhaps our results will be more effective than
traditional messages in convincing people to have a healthy diet. There is a
psychological payoff now from fruit and vegetables -- not just a lower health
risk decades later."
The authors found that alterations in fruit and vegetable intake
were predictive of later alterations in happiness and satisfaction with life.
They took into account many other influences, including changes in people's
incomes and life circumstances.
One part of the study examined information from the Australian
Go for 2&5 Campaign. The campaign was run in some Australian states which
have promoted the consumption of two portions of fruit and five portions of
vegetables each day.
Antioxidants
The academics think it may be possible eventually to link this
study to current research into antioxidants which suggests a connection between
optimism and carotenoid in the blood.
However they argue that further research is needed in this area.