Eating ultra-processed foods (UPFs) such as sugary cereals, fizzy drinks and ready meals have been linked with 32 harmful health effects.

UPFs are usually higher in fat, sugar and salt and contain chemicals, colourings, sweeteners and preservatives that extend shelf life.

An umbrella review conducted by academics in Australia analysed 14 review articles published in the last three years which associated UPFs with poor health outcomes.

These included 9.9 million people, with data on exposure to UPFs coming from the likes of food questionnaires and dietary history.

The team graded the evidence on convincing, highly suggestive, suggestive, weak or no evidence.

What did the research show?

Based on “convincing” evidence, a higher UPF intake was associated with a 50% greater risk of death from cardiovascular disease, a 12% greater risk of type 2 diabetes, and a 48-53% greater risk of developing anxiety.

There was also “highly suggestive” evidence that eating more UPFs could increase the risk of obesity, type 2 diabetes, sleep problems and dying from heart disease by 40-66%, as well as a 22% greater risk of developing depression and a 21% greater risk of death from any cause.

Researchers said that the evidence between UPF intake and “asthma, gastrointestinal health, some cancers, and intermediate cardiometabolic risk factors remains limited and warrants further investigation”.

Craven Herald: UPFs contain chemicals, colourings, sweeteners and preservatives that extend shelf lifeUPFs contain chemicals, colourings, sweeteners and preservatives that extend shelf life (Image: Getty Images)

Previous studies have linked UPF to poor health, but no comprehensive review has yet provided a broad assessment of the evidence in this area.

Some experts not involved in the research highlighted that much of the research included in the umbrella review was weak and also cautioned that the findings do not prove cause and effect.

As reported in The Guardian, Dr Chris van Tulleken, an associate professor at University College London and one of the world’s leading UPF experts, said the findings were “entirely consistent” with prior works.

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He explained there was now an “enormous number of independent studies which clearly link a diet high in UPF to multiple damaging health outcomes including early death”.

“We have good understanding of the mechanisms by which these foods drive harm,” he added. “In part it is because of their poor nutritional profile – they are often high in saturated fat, salt and free sugar.

But the way they are processed is also important – they’re engineered and marketed in ways which drive excess consumption – for example they are typically soft and energy dense and aggressively marketed usually to disadvantaged communities.”