The truth about five a day revealed by doctors – and what you really need to eat to reduce your risk of cancer

Three weeks without a single green vegetable. A month without consuming any fruit. The only pulses? Tinned baked beans.

This, according to a survey published earlier this month, is the diet of the average Briton.

It’s a far cry from ‘five-a-day’ – the five daily portions of fruit and vegetables that the NHS recommends is needed to keep us healthy.

That guidance, designed to stave off heart disease and cancer, has stood for more than two decades and is highlighted regularly in public health campaigns. But only about one-third of women and a quarter of men achieve it, official data shows.

And it’s become even less possible for many as in recent years the price of fresh produce has gone up by an average of 39 per cent – with carrots increasing by as much as 150 per cent.

Leading diet guru Professor Tim Spector who founded the Zoe nutrition app, recommends a different approach to five-a-day with 30 different types of plant every week

As a result, GP leaders have warned of a rise in common Victorian diseases, such as scurvy, which is caused by a deficiency in vitamin C.

Figures unearthed by The Mail on Sunday suggest the number of people being diagnosed with serious nutritional deficiencies has risen by 68 per cent in just two years, from 7,878 in 2020 to 13,286 in 2022.

There is little doubt that fruit and vegetables are essential. But given we’re struggling to meet that five-a-day target, just how important is it?

Some studies have suggested it doesn’t go far enough and that we need to double it for the optimal benefits. Meanwhile, leading diet guru Professor Tim Spector, who founded the Zoe nutrition app, recommends a different approach with 30 different types of plant every week.

However, other studies have found that evidence for the health claims of five-a-day remains weak.

Gunter Kuhnle, professor of nutrition and food science at the University of Reading, says reaching the target offers ‘no magical advantage’.

‘Studies show that people who eat the most fruit and veg fare better when it comes to diseases like cancer and heart disease, compared with those who eat the least,’ he says. ‘But there are things we don’t know. Is it the fruit and veg itself which does that? Are there specific compounds some of them contain which we haven’t been able to pin down?

‘Or is it more about what we’re not eating – that those piling their plates with fruit and veg have less room in their diets for sugary, salty, processed foods?’

He adds: ‘The beneficial effects reported are also relatively modest. There’s an ongoing discussion within the nutrition community – given we think fruit and veg have health benefits, why don’t we find bigger advantages in research?

The ‘five-a-day’ is the the five daily portions of fruit and vegetables that the NHS recommends is needed to keep us healthy

‘It’s sensible to tell people to eat more fruit and veg generally. But in terms of this specific level that you should consume, I doubt the five-a-day rule is accurate.’

Last week, our resident GP Dr Ellie Cannon wrote of her shock at the results of a poll carried out by diet recording app MyFitnessPal. When she asked readers whether they met the five-a-day target, the responses were mixed.

Some, such as 79-year-old Gail Hields, said they manage to get their fill of fruit and veg most days. She says her diet includes a variety of fruit, including grapefruit, melons, apples, bananas and oranges, as well as vegetables as varied as carrots, cauliflower, sprouts, beans and leaks.

‘We’ve even got a stock of vegetables in the freezer in case we run out of fresh,’ she says. ‘I’m not overweight – and while I do have some minor things wrong, these are mainly due to age rather than bad diet.’

Others, such as Peter Mansfield, 84, say he increased his fruit and veg intake later in life, after he spent time in Spain and began to follow a Mediterranean-style diet. ‘I’ve been eating salads ever since,’ he says. ‘It might sound a bit boring but I really enjoy it.’

But not all achieve the five-a-day target. Sheelagh Davidson, 92, says she ‘rarely eats vegetables or fruit’ and eats ‘meat most days’. However, she says her blood pressure is ‘perfect’ and claims she is proof that ‘there is no benefit from eating loads of veg’.

The five-a-day campaign was launched by the Government in March 2003 and linked fruit and veg consumption to reducing the risk of cardiac diseases, cancers and diabetes. 

There are claims it stemmed from a 1980s marketing campaign by Californian farmers but this is only partly true – in fact, health officials in the US state asked the agriculture industry to partner with them on a campaign to boost fruit and veg intake which would be ‘mutually beneficial’.

In 2002, a World Health Organisation taskforce attributed 2.7million annual deaths globally to low fruit and veg intake. Its report found that eating more might ‘play some protective role’ in stopping the development of some cancers. It also noted low rates of heart disease and cancer in what is described as the ‘Blue Zone’ – parts of southern Italy, Greece and Japan – where people eat more fruit and veg and are generally healthier in old age.

The five-a-day campaign was launched by the Government in March 2003 and linked fruit and veg consumption to reducing the risk of cardiac diseases, cancers and diabetes

But it based its guidance on China, which brought in a 400g daily goal to provide a ‘balanced and sufficient intake’. This translated in the UK to five different portions – each around 80g – every day. Ultimately, this was considered ‘easy to remember’ and not too unachievable.

‘There’s an element of psychology and easy marketing,’ says Professor Kuhnle. ‘Other countries have different numbers and portion sizes, but five is a nice easy number for people. Make it higher and it feels harder, and some people give up without even trying.’

As a guide, 80 grams is equivalent to one apple, two satsumas, 14 cherries, six broccoli florets, two heaped spoonfuls of spinach, two handfuls of salad leaves or three tablespoons of peas.

It also includes legumes such as chickpeas, lentils, tofu and baked beans. Potatoes, however, don’t count because they are ‘generally used in place of other sources of starch, such as bread, pasta or rice’, the NHS says.

‘They don’t have to be fresh,’ says dietician Dr Duane Mellor, from Aston Medical School. ‘Frozen, canned, dried or juiced all count.’

Evidence underpinning five-a-day has been conflicting. In 2010, a US report found the link to a reduced risk of cancer was ‘weak’. Researchers found it was only really effective in heavy drinkers – and even then, benefits might apply only to cancers caused by alcohol and smoking, such as in the gut, throat and mouth.

Meanwhile, in 2014, University College London reported that people should consume seven portions if they wanted to drive down their risk of the disease.

And Imperial College London researchers found in 2017 that the ‘greatest benefits’ for preventing a range of serious diseases came from ten a day.

This was linked to a 24 per cent reduced risk of heart disease, a 33 per cent reduced risk of stroke, and a 13 per cent reduced risk of cancer. Despite sounding impressive, these are small reductions.

Someone with a ten per cent risk of developing heart disease who increased their intake from zero to ten portions a day might only reduce that risk to 7.6 per cent.

‘The question is whether all the effort is worth it,’ says Professor Kuhnle.

It’s important to note papers such as these are observational – relying on people to report the details of their diet themselves (experts say they typically over-estimate how much fruit and veg they consume) and then scientists analyse their medical records years later to see if they developed diseases.

Researchers cannot confirm whether more fruit and veg actually lowers the risk of disease or whether something else is at play.

‘People who can afford to eat well are often healthier generally and less likely to be obese and to smoke and drink heavily,’ Professor Kuhnle adds.

Figures unearthed by The Mail on Sunday suggest the number of people being diagnosed with serious nutritional deficiencies has risen by 68 per cent in just two years, from 7,878 in 2020 to 13,286 in 2022

Few clinical trials have been carried out. But one British trial of more than 200 people did look at whether following national dietary recommendations had benefits.

One group was asked to follow a diet which involved eating five portions of veg and fruit, lean meat, oily fish and wholegrains. Another group followed a more typical British diet of white bread, pasta and rice, and only two portions of fruit and veg.

Those on the recommended diet saw ‘significant’ reductions in their blood pressure and cholesterol – especially LDL, the type of cholesterol which is linked with heart disease. But this was only a 12-week study and didn’t follow people in the longer term.

‘We do know fruit and veg contains different types of fibre which is good for bowel health,’ says Dr Duane Mellor. ‘Some may alter or reduce cholesterol absorption and make us feel fuller for longer.

‘There are also other positive things in there, from vitamins and minerals like calcium, which can lower blood sugar, and antioxidants which might stimulate our gut and liver to produce beneficial compounds.

‘Studies show that if you have a higher intake of fruit and veg, the risk from eating red or processed meat reduced. Ultimately, a balanced diet is a good thing.’

And a diet routinely lacking in fresh produce has implications, according to Professor Kamila Hawthorne, chairman of the Royal College of GPs.

‘In the past year we have seen spikes in conditions linked to poor nutrition – including diseases that should have been confined to the past, like scurvy, and folic acid deficiency,’ she says.

‘Poor diet can increase a patient’s risk of developing certain conditions but also exacerbate existing conditions. We have seen fresh foods spike in price, along with energy costs for cooking, making a nutritious diet more challenging for some, while fast foods are cheap and easy to access but low in nutritious content.’

There are also risks to following restrictive diets which cut out whole food groups, such as the meat-only diet.

This has been popularised on social media and by celebrities including psychologist Jordan Peterson and influencer Andrew Tate. There are claims it eliminates health problems, increases focus, and clears the skin.

Experts say there is no evidence to back this up, and singer James Blunt, who tried it for eight weeks at university, says he was diagnosed with scurvy.

‘Quite a few nutrients, such as vitamin C, are hard to get from non-plant sources, and there’s less fibre. In the longer term, this won’t be good for you,’ says Dr Mellor.

But on the flip side, there may be a plateau effect – a point at which the benefits of eating more fruit and veg don’t get any greater.

Researchers from Harvard Medical School found that although eating more fruit and veg was linked with a lower risk of dying from any cause, there was no benefit from eating more than five portions a day.

Experts suggest that the best approach is to consume a range of different fruit and veg – and to tip the balance in favour of veg, which generally contains more fibre and less sugar. It’s the idea that variety is good which led to Professor Tim Spector’s 30-a-week proposal.

A 2018 study by the British and American Gut Project, which he ran, found that people who eat a wide variety of plant foods – fruit and veg, but also seeds, nuts, wholegrains and spices – have more diverse bacteria in their gut.

This has been linked with better overall health, from brain function to the immune system.

But Professor Kuhnle says: ‘I’m sure it’s good, but whether it significantly improves the benefit beyond five-a-day is unclear.’

However, there are still benefits from eating smaller amounts.

The same study found a daily intake of 200g – just under three portions – was linked to a 16 per cent reduced risk of heart disease, and a four per cent reduced risk of cancer. Even premature death was slashed by 15 per cent.

‘Very often what matters is doing something, rather than nothing,’ Professor Kuhnle says. ‘Spending time fixating on eating the right things, when the benefits aren’t perhaps enormous, isn’t helpful.’

It’s a fact…

A 2018 study found that fresh vegetables and salad make up a quarter of edible household food waste in the UK. 

Easy peas-y or just too much – your views on a healthy diet

My husband and I absolutely love fruit and veg. People who don’t eat much are really missing out.

On a typical day we’ll eat pineapple, melon and some frozen mixed berries for breakfast. Then we’ll have homemade vegetable soup for lunch, or salad in the summer.

Then, at dinner, our favourites are Mediterranean vegetables, such as courgette, aubergine, red onion and cherry tomatoes. It’s so easy to throw everything in with some olive oil and roast it in the oven.

Bobbie Gristwood, 66, from Warwick

Five handfuls of fruit and vegetables a day is just too much. I eat three meals a day and don’t snack. When I do eat, I get plenty of protein and a handful of vegetables with each meal. But I don’t have room for five portions.

Leanda von Halle, 66, from London

I have always believed that the claim we need five portions of fruit and vegetables a day was invented to increase the profits of producers.

Is there evidence to support the claim that eating this much improves your overall health? Obviously, I’m sure it won’t do any harm, but I feel the importance isn’t supported by any actual data.

Richard Wilde, 69, from Merseyside

Experts suggest that the best approach is to consume a range of different fruit and veg – and to tip the balance in favour of veg, which generally contains more fibre and less sugar

I don’t eat fruit and veg apart from some sultanas on my breakfast cereal, and occasionally some raspberries or strawberries with double cream or ice cream.

As for vegetables, I have peas with meals about twice a day, and if my wife makes a casserole it will usually include mushrooms, tinned tomatoes and onions. However, I don’t eat fast food or takeaways and I’ve never been to a McDonald’s.

Martin Faherty, 76, from North Devon

I was always aware I should have five portions of fruit and vegetables a day, but it wasn’t until a recent operation on my foot, which left me stuck at home for seven weeks, that I really focused on achieving it.

I now hit the target every day. Most days I will have a glass of unsweetened orange juice, a banana and some cherry tomatoes. From there it’s relatively easy to add two more portions.

Sara Crowcroft, 57, from Wakefield

I grew up in Portland, Oregon, and we had a vegetable garden and ate a variety throughout the year.

My husband was raised in Fife, Scotland, and I will never forget eating with his family for the first time and seeing nothing green on the table.

Luckily, my husband was not adverse to changing his eating habits and now we very seldom go a day without vegetables like kale, broccoli, brussels sprouts and asparagus, as well as fruits like kiwis, apples and pears.

He’s proof that it’s never too late to get your five-a-day.

Tam Hume, 70, from the Scottish Borders

I have always eaten at least one piece of fruit a day and now, in my older years, I eat three to four pieces a day, including an apple (to keep the doctor away).

I also eat regular veggies, which my wife insists I have due to my type 2 diabetes.

Darryl Annis, 71, from Gloucestershire