Last updated by Dr Sarah Brewer on
Do you aim to eat 5 servings of fruit and vegetables per day? Is there any evidence that this is the right amount? The famous 5-a-day phrase originated in the late 1980s in a Californian ‘5-A-Day For Better Health’ campaign. It was soon adopted by the National Cancer Institute (NCI) whose eventual goal was to increase Americans’ consumption to first five, and then nine servings of fruit and veg on a daily basis.
Additional support came from the World Health Organisation, who stated that insufficient consumption of fruit and veg was a key driver of non-communicable diseases such as heart attack, stroke, diabetes and cancer. They even estimated that globally, an astonishing 2.7 million lives were lost, each year, as a direct result of low intakes and recommended aiming for 400g fruit and veg a day – five 80g portions, not counting potatoes.
Where was the evidence?
From the start, the 5-a-day and 9-a-day programs were based on ‘a substantial body of opinion’ but very little proof. The large EPIC (European Prospective Investigation into Cancer and Nutrition) trial provided preliminary data that fruit protected against bowel cancer in women (but not in men) and against lung cancer (although vegetables did not).
It was only after 13 years worth of follow-up that evidence of a dose-response was confirmed in late 2014. Those eating more than 569g of fruits and vegetables (around 7 portions) in the EPIC study were 15% less likely to have died from circulatory disease, 27% less likely to have died from respiratory disease, and 40% less likely to have died from digestive system disease when compared with those eating less than 249g/day (3 portions).
The protective effects were generally seen with vegetables rather than fruit, and were more pronounced when these were eaten raw rather than cooked.
A few months before these results were published, analysis of the Health Survey for England data (involving 65,000 people followed for an average of 8 years) showed that eating at least 7 portions of fresh fruit and veggies a day was associated with a 25% lower risk of cancer, and a 31% lower risk of heart disease or stroke. What’s more, those consuming 7 or more servings per day were 42% less likely to have met the Grim Reaper during the study period than those eating 6 or less. Headlines immediately called for everyone to start eating 7-a-day as 5-a-day was obviously no longer enough.
Or was it?
Why not 7-a-day?
A long-awaited meta-analysis was recently published in the British Medical Journal. This pooled data from 16 prospective studies conducted throughout Europe, Asia and Scandinavia and involved 833,234 participants with follow-ups ranging from 4.6 to 26 years. These results supported the theory that a higher consumption of fruit and veg is associated with a reduced risk of mortality from just about every cause, including heart disease and stroke, but still did not confirm a protective effect against cancer.
- Each extra portion of fruit per day reduced the overall risk of death by 6% and the risk of a cardiovascular disease by 5%.
- Each additional portion of vegetables per day reduced the risk of death by 5% and the risk of a cardiovascular death by 4%.
There was a clear threshold at five servings of fruit and veg a day, after which the risk of all-cause mortality did not reduce any further. This association remained after accounting for other confounding factors such as exercise, energy intake, education and income.
So where does this leave us?
The best evidence to date appears to confirm that eating 5-a-day offers clear health benefits against the risk of death from heart disease or stroke, but not from cancer. And while previous emphasis was all about eating more vegetables rather than fruit – because of concerns about the level of natural fruit sugars present – fruit may actually offer more protective than veggies, even if only slightly.
I would suggest you:
- Do your utmost to achieve 5-a-day, on most days
- Ignore headlines urging you to eat 7-a-day or more – unless you actually want to, and find this easy
- Don’t feel guilty about selecting 3 fruits and 2 veggies, rather than the other way round, if you prefer them
- Aim to eat your vegetables raw, or only lightly steamed or stir-fried, where at all possible…
… at least until the next review of the evidence turns everything back on its head again!
How much fruit do you eat? Do you manage your 5-a-day, or do you eat less or more?
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