Is all ultra-processed food bad for you?

Ultra-processed foods have been in for some serious bad press recently, with their consumption linked to a range of illnesses including obesity, cancer, depression and dementia.

In the UK, ultra-processed food (UPF) makes up an estimated 60% of our diets, so you can see why there are concerns. But is a lunch of baked beans on toast (made from supermarket bread) the same as a packet of biscuits?

The group of foods that fall into the UPF category is incredibly broad and writing them all off is neither necessary nor practical for many. 

There's no doubt we should all aim to eat more whole foods (food close to its natural state) and limit the amount of foods high in fat, sugar and salt in our diet. But cooking from scratch all the time isn't realistic or practical for everyone.

What does the evidence show?

A paper published in the BMJ in February 2024, looked at the existing evidence of associations between UPFs and health outcomes and was reported widely in the press. 

This was an 'umbrella review' where researchers looked at 45 existing meta-analyses, they did not include any new evidence. 

The review found evidence that higher intakes of UPFs were associated to an increased risk of adverse health outcomes. These included cancer, cardiovascular disease, type 2 diabetes, mental health and respiratory problems as well as early death.

However we still can't pinpoint what it is about UPFs that are responsible. Is it that they tend to be high in fat, sugar and salt and low in protein, fibre, vitamins and minerals? Or is it the preservatives and emulsifiers that are in them? 

This review and previous studies don't tell us, and while we can say there is an association between UPF intake and adverse health outcomes we can's say UPF cause disease. 

The researchers of this study acknowledged there were limitations to the review and other experts have been critical of some of the research included, saying it was weak and of poor quality.

It's good that research into UPF is ongoing but until we know more it seems premature to dismiss all UPFs, especially as it's a category that includes such as wide range of foods. 

Keep reading to see the UPF foods that can be part of a healthy diet.

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Supermarket bread

Baking your own bread or buying a bakery loaf - often costing more than £4 - isn't an option for many, whereas it's possible to pick up a supermarket loaf for 75p.

Supermarket bread is in the UPF firing line because it contains emulsifiers and preservatives. These improve the texture and extend the shelf-life of bread, but also push it into UPF territory.

Two slices of supermarket wholemeal bread provide around 16% of your daily fibre needs and are a good source of vitamin B1. 

The loaf you choose matters though. Wholemeal is preferable, because it has more fibre, and seeded wholemeal bread is even better as seeds further increase the fibre and protein content, as well as healthy unsaturated fats. 

These tend to be a bit pricier than basic bread, but offer a good compromise between health and cost. Supermarket versions are widely available, such as Tesco's Wholemeal Seeds and Grains bread, (£1.35 for 800g)

For more control over what's in your bread, why not bake your own the easy way? Discover the best home bread making machines

Breakfast cereals

There's a dizzying array of breakfast cereals available and not all are created equal. 

Some are rightly vilified as junk. Many cereals are packed full of sugar, despite spurious marketing claims which make them appear a healthy choice.

But plainer, simpler cereals can be a healthy breakfast choice. 

All-Bran, Bran Flakes and Weetabix are all high in fibre and contain a mix of important vitamins and minerals. They're classed as ultra-processed because they contain barley malt extract and/or glucose syrup. These are both types of sugar, but are present in relatively low amounts.

Muesli is also considered a UPF as it contains skimmed milk and milk whey powders.

Picking plainer style cereals, and topping with whole foods such as fruit and nuts, can be a healthy breakfast choice.

What you need to know about cereal portion sizes - why manufacturer recommendations don't stack up with reality

Baked beans

Baked beans are a convenient and relatively cheap way to get a fibre and protein boost. 

As well as being low in sugar and fat, half a tin counts towards one of your five-a-day of fruit and veg, and contains as much protein as two small eggs.

Most baked beans are classed as ultra-processed as they contain modified cornflour or starch, and spice and herb extracts. Heinz organic baked beans don't, so aren't UPF.

We don't eat enough lentils and beans, and from a nutrition perspective they're a good addition to your diet. 

Find out which cheap supermarket baked beans beat Heinz in our consumer taste test

Fish fingers

Many of us don't meet the government guidelines of eating two portions of fish a week. 

A serving of fish fingers counts towards this target and, although it's not an oily fish, white fish is a good source of lean protein and is low in fat.

Look for a higher fish-to-bread ratio for a healthier choice.

Find out which supermarket fish fingers were rated the tastiest in our fish finger taste test.

Plant milks

Plant milks are often the only alternative for people with dairy allergies or lactose intolerances. 

But they're considered UPF as they contain added vitamins and minerals, acidity regulators, stabilisers and flavourings. 

Other than soya milk, most plant milks are low in protein. And to nutritionally match cow's milk, plant milks need to be fortified with vitamins and minerals. 

If your using plant milk to replace all the cow's milk in your diet it's important to choose a non-organic version as organic milks can't be fortified, and some nutrients, such as iodine, are hard to get from elsewhere in your diet.

See our guide to which plant milk is best for your health and the environment.

Pasta sauces

A jar of tomato pasta sauce typically contains acidity regulator and thickener, which is why they are classed as ultra-processed food.

But combined with pasta, it can make a quick budget-friendly meal when you're pushed for time.

Adding some veg, mince, lentils or tinned tuna increases the fibre, protein and vitamin and mineral content for well-balanced meal. 

Yoghurt

Yoghurt is a good source of calcium which is important for bone health and teeth. It also often contains live bacteria which are good for gut health.

Like cereals, it's a real mixed bag - some can be high in sugar and additives, so you need to choose wisely.

Plain Greek and Greek-style yoghurts and natural yoghurts are good options but sometimes even these can fall into the UPF category as they may contain thickeners such as pectin.

Those containing fruit compote or purée are also UPF as the fruit often contains thickeners or starches.

Opting for plainer versions is best, and adding your own fruit or nut toppings. Typically, the further removed from a plain or fruit flavour it is (eg toffee crunch), the more likely it is to be packed with additives, sugar or sweeteners.

Houmous

Houmous is traditionally made by blending chickpeas, olive oil, tahini, garlic, lemon juice and salt.

Shop-bought versions contain preservatives and acidity regulators which help to prolong the shelf-life and keep it safe, but also push it into UPF territory.

While eating houmous isn't as beneficial as eating whole chickpeas (they contain more fibre and will make you feel fuller) it's still a good source of vegan protein and contains healthy unsaturated fats. 

What is ultra-processed food?

Typically ultra-processed foods tend to be lower in beneficial ingredients and nutrients such as fruit and veg, fibre and protein, and higher in less-preferable nutrients such as sugar, fat and salt. They are usually energy dense and highly palatable (easy to over-consume).

However this doesn't apply to all UPFs, which are a very broad range of foods. As the examples above show, a relatively small addition can push an otherwise healthy food into UPF territory.

The risk of tarring all UPF with the same brush is people focus on the wrong foods, cutting out those that make a valuable nutritional contribution instead of cutting out the foods high in sugar, fat and salt which we know we should eat less of. Or, that they get put off altogether by the limitations.

What are the risks of diets high in UPF?

A number of recent studies have linked diets high in ultra-processed foods with an increased risk of a range of 'adverse health outcomes' - diseases and health conditions including obesity, cancer, irritable bowel disease, Type 2 diabetes, depression, dementia, high blood pressure, heart attacks and stroke. 

Clearly, there's cause for concern here. However, most of the current evidence is based on observational studies - when people report on what they did or what they ate over a period of time and researchers link this to their health.

These studies rely on people accurately recalling and reporting on what they ate, often months or years after the event took place.

Observational studies can show a link or correlation between behaviours and outcomes but they can't definitively prove cause and effect.

A 2019 Randomised Controlled Trial (RCT) in the US on 20 participants showed individuals consumed more calories and gained weight when eating a diet based on ultra-processed foods versus one consisting of unprocessed food. 

The meals and snacks in both groups were matched for calories, carbohydrates, protein, fat, sugar, salt and fibre and participants were allowed to eat as much as they wanted.

The UK Scientific Advisory Committee on Nutrition (SACN) carried out a review of the existing evidence on UPFs in 2023 and concluded that more research was needed before we could definitely link consumption of UPFs to negative health outcomes, due to variations in how other lifestyle factors were accounted for between studies, and in defining what counts as ultra-processed food. 

How to approach UPFs

No single food is going to save or sink your diet. In the same way that ‘superfood’ benefits are often overstated, consuming some UPFs is unlikely to be make or break – and some can be helpful in shoring up our diets and providing important nutrients.

However, there are some UPFs that you already know you shouldn’t eat too much of - typically these are highly processed products high in fat, sugar and salt (HFSS), such as crisps, biscuits, ice creams, cakes, chocolates and sugary drinks.

Here, government regulation and food companies have a role to play. Many of these foods are described as ‘hyper-palatable’ and easy to over consume. Clever marketing often works to gives them a health ‘halo’, too.

It’s disappointing that the government has continually delayed a proposed ban on advertising HFSS foods, despite some supermarkets voluntarily introducing it and calling for improved regulation. 

For now, as individuals, it's worth taking stock and considering the quality of your overall diet. Try to eat whole foods where possible, and limit UPFs that are high in fat, sugar and salt, using traffic light labelling as a guide.