Parents all over the world are constantly telling their kids to eat their veggies “because it’s good for you”. Studies have long shown that the risk of cancer and heart attacks can be greatly reduced by a regular intake of fruit and vegetables. Recent research done at University of Warwick went beyond the traditional scope in an attempt to explore the psychological well-being effect of eating extra – up to 8 portions – of fruit and vegetables per day.

The results of the research show that people can experience an increase in life satisfaction to the same degree as moving from unemployment to employment would bring, simply by changing their lifestyle from eating almost no fruit and vegetables at all to up to eight portions a day. The overall positive health changes were noticed within 24 months.

Large positive psychological benefits were experienced by the more than 12,000 randomly selected people that took part in the study. The subjects’ psychological well-being was measured and they were expected to keep food diaries.

Andrew Oswald, Professor of Economics and Behavioural Science at the University of Warwick, also observed that physical-health benefits such as cancer protection only accrues decades later, while eating fruit and vegetables boosts happiness far more quickly, with other large psychological and health benefits already observed after a short 2 years. This should strengthen people’s motivation to eat healthy food considerably.

The happiness effect is cumulative up to eight portions per day – it increase incrementally for each extra daily portion of fruit and veggies. During the research, done in 2007, 2009, and 2013 and involving 12,385 randomly sampled Australian adults, the teams from the University of Queensland, Australia and the University of Warwick, England, adjusted the effects on incident changes in life satisfaction and happiness to take into account personal circumstances and changing incomes.

In the developed western world, the typical citizen eats an unhealthy diet and the results of this study could very well be used to persuade people to consume more fruits and vegetables. As such, it becomes an important tool in the knowledge base for health professionals. Not only does healthy eating now result in just a lower health risk decades later, but the payoff from eating fruit and vegetables becomes apparent almost immediately. Dr Redzo Mujcic feels that these results could be more effective in convincing people to have a healthy diet than traditional messages.



The campaign was run in some Australian states with the “Australian Go for 2&5 Campaign”. This campaign promotes the consumption of two portions of fruit and five portions of vegetables every day. An interesting aspect of the study to note is that alterations in fruit and vegetable intake could be used to predict later alterations in happiness and satisfaction with life. Other influences such as changes in people’s life circumstances and incomes were taken into account during the research.

This study could be a link to current research into antioxidants which suggests a relation between optimism and carotenoid in the blood. To prove this correlation, further research is needed.

The full study was published in American Journal of Public Health.