You’ve probably heard this many times:

“Eat at least five portions of fruit and vegetables a day.”

But you might wonder: Is that really necessary? Why five? What’s the science behind it? Let’s explore.

What is “five a day”? And what counts?

First, let’s clarify what people mean by “five a day.”

In the UK, a “portion” is generally defined as 80 grams of fruit or vegetables (fresh, frozen or canned) (or the equivalent) (GOV.UK).

Dried fruit counts too, but a smaller weight (about 30 grams dried is considered one portion) because it’s concentrated. (goodmedicine.org.uk)

For 100% fruit or vegetable juice / smoothies: only 150 ml counts as one portion, no matter how much you drink beyond that. Because juicing removes fibre and concentrates sugars. (GOV.UK)

Some items don’t count: typical potatoes, yams, cassava and plantain are classed as starchy foods, so they are excluded from the 5 a day (though sweet potatoes, squash, etc. do count) (goodmedicine.org.uk).

So “five a day” is shorthand for at least five portions of a variety of fruit and vegetables, about 400 g total.

This is not a perfect rule, but a simple, memorable target.

Where did “five a day” come from?

The “five a day” message comes from public health guidelines internationally (including in the UK). It’s based on epidemiological evidence linking higher intake of fruits and vegetables with lower risks of chronic diseases — such as heart disease, stroke, some cancers, and improved overall mortality. (goodmedicine.org.uk)

In the UK, the 5 a Day campaign is tied to recommendations from bodies like Public Health England and is aligned with the World Health Organization’s guideline that suggests a minimum of 400 g of fruit and vegetables a day (excluding starchy roots) for health benefits. (PMC)

In policy papers, the government states that eating more than 400 g/day is associated with reduced risks for diet-related chronic diseases (not including potatoes). (GOV.UK)

So “five portions” is a practical way of saying “around 400 g or more of fruit + vegetables daily.”

What benefits do we see? And is “five” enough?

Evidence for benefits

Many studies (observational and some intervention ones) find correlations between higher fruit/vegetable intake and lower risks of:

• Heart disease
• Stroke
• Type 2 diabetes
• Certain cancers
• All-cause mortality (i.e. living longer)
• Better weight management
• Improved gut health (via fibre)
• Better micronutrient intake (vitamins, minerals)

When people consume more fruits and vegetables, they tend to replace other less healthy foods — more processed, sugary or fatty ones — which also helps.

A modeling study on the UK estimated that if the population met the 5 a Day target, average life expectancy could increase by 7–8 months, thanks to reductions in diet-related disease burden. (PMC)

However, many studies also suggest that “more is better” ****beyond five portions there continue to be gains (though with diminishing returns). For example, meta-analyses show that eating twice that (around 800 g) offers additional protection for mortality risk.

So five is a baseline, but not necessarily the upper limit of benefit.

Practical tips to hit your “five”

• Try to spread portions through the day, don’t cram them all in one meal.
• Use colourful varieties (“eat the rainbow”) so you get different nutrients.
• Keep frozen/canned options handy (without too much added salt/sugar).
• Sneak vegetables into sauces, soups, stews.
• Use fruit as snacks or desserts.
• Use smoothies or juice smartly (remember the limit of 150 ml).
• Try new fruits/veg you’re less familiar with to increase variety.