July 14, 2016 -- Eating up to eight servings of fruit and vegetables a day could make you feel happier, new research suggests.
Experts have long recommended a diet with lots of fruits and vegetables to help guard against cancer and heart disease. But, researchers say, it’s hard to persuade people to eat more fruits and vegetables today when the benefits aren’t seen for years or even decades.
However, improvements to your mood may be seen within 2 years, they say.
Scientists from the universities of Warwick and Queensland in the U.K. and Australia looked at food diaries kept by 12,385 Australian adults. The people, who were chosen at random from a large Australian survey, had also had their psychological well-being measured.
The researchers discounted effects such as changes in personal circumstances and income that could have influenced how happy the people felt.
They found that about 85% of participants had fewer than three daily servings of fruit, while 60% ate fewer than three daily servings of vegetables. Only a very small percentage of people (1.83%) ate, on average, more than five servings of fruit. Only 7.75% ate more than five servings of vegetables.
The study, to be published in the August issue of the American Journal of Public Health, found that improvements in happiness were seen for each extra daily portion of fruit and vegetables, up to eight portions a day.
The researchers conclude that people who go from eating almost no fruit and veggies to eight servings every day would have an increase in life satisfaction equivalent to moving from unemployment to employment. That improvement would be seen within 24 months, they claim.
"People’s motivation to eat healthy food is weakened by the fact that physical-health benefits, such as protecting against cancer, accrue decades later,” Andrew Oswald, professor of economics and behavioral science at the University of Warwick, says in a statement. “However, well-being improvements from increased consumption of fruit and vegetables are closer to immediate."
The researchers speculate that 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. Carotenoids give fruit and vegetables their distinctive red, yellow, and orange colours.
They say that further research is needed in this area.
Only about 1 in 10 Americans eats enough fruits and vegetables, the CDC said last year. Just 13% of people in the U.S. eat 1 1/2 to 2 cups of fruit daily, as recommended by federal dietary guidelines, and less than 9% of Americans eat 2 to 3 cups of vegetables as recommended.
The British Dietetic Association says there is evidence to show that every serving of fruit and vegetables eaten daily can reduce the risk of strokes by up to 40% and some cancers by up to 20%.