4th August 2014
Five daily portions of fruit and vegetables may be enough to lower risk of early death
Eating five daily portions of fruit and vegetables is associated with a lower risk of death from any cause, particularly from cardiovascular disease – but beyond five portions appears to have no further effect, finds a new study.
These results conflict with a recent study published in BMJ's Journal of Epidemiology and Community Health suggesting that seven or more daily portions of fruits and vegetables were linked to lowest risk of death.
There is growing evidence that increasing fruit and vegetable consumption is related to a lower risk of death from cardiovascular disease and cancer. However, the results are not entirely consistent. So a team of researchers based in China and the United States decided to examine the association between fruit and vegetable intake and risk of all-cause, cardiovascular, and cancer deaths.
They analysed the results of sixteen studies involving a total of 833,000 participants and 56,000 deaths. Differences in study design and quality were taken into account to minimise bias. Higher consumption of fruit and vegetables was significantly associated with a lower risk of death from all causes, particularly from cardiovascular diseases.
Average risk of death from all causes was reduced by 5% for each additional daily serving of fruit and vegetables, while risk of cardiovascular death was reduced by 4 percent for each additional daily serving of fruit and vegetables. But the researchers identified a threshold around five servings per day, after which the risk of death did not reduce further.
In contrast, a higher consumption of fruit and vegetables was not appreciably associated with risk of death from cancer. The researchers suggest that — as well as advice to eat adequate amounts of fruit and vegetables — the adverse effects of obesity, physical inactivity, smoking and high alcohol intake on cancer risk should be further emphasised.
Although a threshold of five servings was identified, the team reiterates the importance of regular fruit and vegetable intake, concluding that their study "provides further evidence that a higher consumption of fruits and vegetables is associated with a lower risk of mortality from all causes, particularly from cardiovascular diseases. The results support current recommendations to increase consumption of fruits and vegetables to promote health and longevity."