Can ultra-processed foods cause cancer?

Medical Director for Health Clinics at Bupa UK
20 February 2018

Could eating lots of heavily-processed foods increase your risk of getting cancer? You may have seen this in the news recently, after a new study found there could be a connection. Here I’ll give some more details about the findings and what they could mean for you.

Three red sweets, in plastic wrappers, on a white table

What are ultra-processed foods?

The authors of the new study used this term to describe foods that have gone through a lot of physical, chemical or biological changes from their natural form. They say this could include:

  • mass-produced and packaged bread and buns
  • sweet or savoury packaged snacks 
  • confectionery and desserts
  • fizzy and sweetened drinks
  • meatballs
  • chicken or fish nuggets

The researchers used the term ultra-processed to distinguish these from fresh foods, and also from slightly less ‘processed’ foods such as canned vegetables and cheeses.

What does the study show?

The study tracked the eating habits and health of around 105,000 people. It was found that the more ultra-processed foods people ate, the more likely they were to get cancer. The risk of cancer increased by about 12% when the proportion of ultra-processed food in people’s diet increased by 10%. The authors say they don’t know why this might be the case. They think it could be linked to the lack of nutritional value of ultra-processed foods, the amount of additives in them, or the heating and processing methods used to create them.

How reliable are the results?

Even the authors of the study have said that we can’t draw any definite conclusions from the findings. They say more research needs to be done on a potential link between ultra-processed foods and cancer.

One problem with interpreting the results, for example, is that people in the study who ate more ultra-processed foods were also more likely to be smokers and to do less exercise. These are both factors that we know can be linked to a higher cancer risk.

What we know for sure about diet and cancer

Although this new study doesn’t tell us anything for definite, it’s part of a mounting body of evidence that shows what we eat can affect our cancer risk. Here are some things about diet and cancer that we know with much more certainty.

  • Weight gain. This is one of the most important ways diet can affect your risk of cancer. Being overweight increases the risk of 13 different types of cancer, including bowel cancer and post-menopausal breast cancer. The World Health Organisation says that being overweight or obese is the most important avoidable cause of cancer, apart from smoking.
  • Alcohol. There’s also strong evidence that regularly drinking too much alcohol increases the risk of many types of cancer.
  • Red and processed meat. Too much red and processed meat in your diet increases bowel cancer risk. Processed meat means sausages, bacon, ham and salami.

So what can you do to reduce your risk of cancer? As well as keeping to a healthy weight, and limiting the alcohol and processed meat, there’s good evidence that eating a healthy balanced diet can help. A diet with plenty of fruit and vegetables can reduce your risk of mouth, larynx and lung cancers. You’ll also be getting plenty of fibre in your diet – and that lowers your risk of bowel cancer.

How about some food swaps?

Don’t despair if a food you enjoy is considered ultra-processed. Just try to cut down on it and don’t have it too often. And how about sometimes going for a healthier alternative? You could try swapping:

  • processed bread and buns for freshly baked ones
  • crisps for unsalted nuts and seeds
  • sweets for olives

You could also get some inspiration from out blog about sugar swaps, which includes videos about swapping fizzy drinks and sweets for healthier options.


Here at Bupa we’ve made a promise to our health insurance customers that if they develop cancer whilst with us, we’ll aim to give the best treatment, support and information available.

Dr Luke James
Medical Director for Health Clinics at Bupa UK

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