Just three servings of fruit and vegetables a day can transform your outlook on life, a new study suggests.
The American study, which appeared in the online journal Psychosomatic Medicine this month, examined the link between healthy eating and life satisfaction levels.
It found that those who ate more fruit and vegetables reported higher levels of optimism and a more positive outlook on life.
The study measured the concentration of carotenoids in the blood streams of participants.
Carotenoids are compounds commonly found in plants, and a diet high in fruit and vegetables means a higher concentration of carotenoids in the blood stream.
It found people who reported high levels of optimism had up to 13 per cent more carotenoids.
The study, reported by Medical Daily, found no link between optimism and Vitamin E, which is sourced from wheat- and nut-based foods.
Although the link is promising, it is unclear whether optimistic people tend to choose healthier options, or if their good eating habits are the cause of their positive outlook on life.