Ultra-processed food and cancer

Young woman studies nutrition label of almond milk while shopping in grocery storeUltra-processed food has hit the headlines consistently over the past few years, as ever more concern is raised about its role in the average UK diet and possible health risks.

This includes questions about how ultra-processed food may contribute to the obesity epidemic and potential links to illness and diseases, including cancer. But what actually is ultra-processed food and how much of a risk does it pose to our health?

What is ultra-processed food?

Quite simply, ultra-processed food is a food product you can’t recreate in your own kitchen. This is because it contains industrial substances and other additives that you won’t find on the shelves of your local supermarket to use at home.

Much of our food undergoes some sort of processing before it reaches the home: milk, oil, flour, tinned tomatoes, butter, frozen fruit and veg all require an element of processing, but ultra-processed food is very different.

A 2018 study found that more than half of the calories that an average person in the UK eats come from ultra-processed food. Ultra-processed products commonly consumed in the UK include processed meat, veggie burgers, crisps and biscuits.

How do I spot ultra-processed food?

The easiest way is to look at the ingredients list on a product. If it includes something you don’t recognise, and if the list is longer than 5 items, it’s most likely ultra-processed.

Look out for substances like maltodextrin, fructose, corn syrup, invert sugar, modified starches, soy protein, casein, lecithin, hydrolysed proteins, Xanthan gum, mono- and diglycerides of fat acids, and hydrogenated or modified oils.

Additives used to make the product taste more appealing include preservatives, flavour enhancers, emulsifiers, thickeners, and artificial colours, or colourants, flavours or sweeteners.

Be careful

There are some ingredients that you may not recognise but which don’t mean the food is ultra-processed. Examples include ascorbic acid (another name for vitamin C), corn starch, and flour that’s fortified with calcium, iron, thiamine and niacin.

What are the most common ultra-processed foods?

This probably won’t surprise you, but the most common are:

  • Fizzy or sugary drinks
  • Sweets and chocolate
  • Biscuits, pastries and cakes
  • Crisps and other packaged snacks
  • Sausages and burgers, chicken nuggets, packaged pies and pizza
  • Ice cream

These typically all fall into what are known as high in fat, salt and sugar (HFSS) foods. They’re high in calories, but contain few of the nutrients your body needs to be healthy, such as fibre, vitamins and minerals. They’re also formulated to be very tasty, so you’re more likely to eat more of them.

This means you can end up consuming more calories than if you’d eaten an equivalent amount of minimally processed food. However, because of their low nutritional value, you may not feel like you’ve eaten a lot. Food that is typically cheap, highly palatable and widely available or ready-to-eat often replaces more nutritious, unprocessedor minimally processed food in the diet.

There’s another group of ultra-processed food products that don’t fall into the HFSS category. These include:

  • Vegetable-based pasta sauces
  • Sliced wholemeal bread
  • Low-sugar wholegrain cereals
  • Unsweetened fruit yoghurts
  • Unsweetened plant-based fortified milk alternatives

Even though they’re technically UPF, they’re more nutritious because they contain fibre and other beneficial nutrients.

They can be part of a healthy, well-balanced diet and are often easier to prepare and more affordable, which is great for people who are less well-off, don’t have access to proper supermarkets or are limited for time.

Are ultra-processed foods bad for you?

Firstly, we know from research on obesity that the HFSS versions of ultra-processed food contribute towards obesity, because they’re high in calories, but lack the nutrients our body needs to be healthy.

And we know that overweight and obesity is a major risk factor for 13 different types of cancer, plus it increases our risk of heart disease and type 2 diabetes.

A groundbreaking study in November 2023 found that eating more ultra-processed food increases the risk of suffering from 2 or more long-term health conditions including cancer, diabetes and heart disease – known as multimorbidity.

And another study published in November 2023 found that eating more ultra-processed food may be associated with a higher risk of developing cancers of the upper aerodigestive tract (including mouth, throat and oesophageal cancers). We know that eating UPF is linked to obesity, but researchers said that may not be the only factor linking highly processed food with these cancers, and that other factors could be at play, such as additives – including emulsifiers and artificial sweeteners which have been previously associated with disease risk – and contaminants from food packaging and the manufacturing process.

In March 2023, a study co-funded by World Cancer Research Fund found that every 10% increase in ultra-processed food in a person’s diet increased cases of ovarian cancer by 19%, and overall cancer incidence by 2%. Ultra-processed food was also linked to a greater risk of dying from cancer; in particular ovarian and breast cancers.

Another study found that swapping 10% of ultra-processed food with minimally processed food was linked to a reduced risk of 7 types of cancer.

So, for your health it’s best to avoid or limit consumption of ultra-processed foods that are high in fat, salt and sugar.

What ‘can’ I eat to have a healthy diet?

Eating a diet rich in wholegrains, fruit, vegetables and beans should be your starting point. All of these foods are either completely natural or minimally processed. They provide a valuable mix of minerals and nutrients that your body needs to function properly.

Think about filling at least three-quarters of your plate or bowl with vegetables, fruit, pulses (such as beans, chickpeas and lentils) and wholegrains such as brown rice or wholewheat pasta.

The remaining quarter can be lean meat, chicken or turkey, fish, eggs, low-fat dairy products or plant-based proteins, such as tofu and tempeh.

If you want to eat red meat, keep it to no more than 3 portions a week, and avoid processed meat (such as sausages, bacon, ham and chorizo) completely. This will help protect against bowel cancer.

Aim to cook more often at home, making your meals from scratch rather than buying ready meals or pre-made sauces.

If you batch cook – cooking once, but making more than you need for one meal – freeze the unused portions, which will help to ensure you’ve got something when you don’t have the time or energy to cook.

For convenience, you can also use ultra-processed foods that aren’t high in fat, salt and sugar, such as vegetable-based sauces for pasta, in your home cooking.

Cooking at home can also help save you money, as well as improve your overall diet.

We have more than 300 healthy recipes to suit many diets and which have been created to help reduce your risk of cancer.

> Find a healthy recipe to suit your tastes

But I love chocolate …

We’d never suggest banning any food – it’s just better to eat some things in moderation. Balance is the key. The odd chocolate biscuit or packet of crisps isn’t a problem – it’s just that ultra-processed food is more easily overeaten, and some people find it addictive. It’s easy for a small packet of crisps to turn into a 100g grab bag.

Think about your overall diet: try to minimise the amount of foods that are high in fat, salt or sugar, and choose foods that offer you nutrients as well as flavour and enjoyment. While some processed foods may appeal to your taste buds, more nutritious foods can be just as tasty.