A new 30-year study has confirmed what many health experts have been screaming from the rooftops for years: Ultra-processed foods are associated with a slightly higher increased risk of an early death.

On Wednesday, the population-based correlation study was published in the British Medical Journal and found that certain types of processed foods have a “particularly strong associations with mortality”.

For the study, researchers at Harvard TH Chan School of Public Health examined the dietary logs of more than 74,000 female registered nurses in 11 US states and 39,000 male health professionals across the US.

None of the participants had a history of  cancer, cardiovascular disease or diabetes and every two years, starting in the 1980s, they were asked to provide details about their health and lifestyles.

The study found people who consumed more processed foods had an increased risk of dying, when compared to those who had fewer servings of processed foods.

Given the Harvard study spanned more than 30 years, the researchers were able to analyse the causes of deaths.

There were 48,193 deaths (30,188 deaths of women and 18,005 deaths of men) documented, 13,557 deaths were attributed to cancer, 11,416 deaths due to cardiovascular diseases.

There were 6343 deaths due to neurodegenerative diseases and 3926 deaths due to respiratory diseases.

Additionally, the researchers found younger participants tended to consume more ultra-processed foods and they were more likely to smoke but consume less alcohol, were less physically active, had a higher BMI and ate fewer fruits, vegetables and whole grains.

Speaking to the Global Mail, the study’s lead author, Dr Mingyang Song said the association between ultra-processed food and morality was “quite linear”.

However, not all highly processed foods are made equal.

The foods to avoid

The study found that ultra-processed, ready-to-eat products that were meat, poultry or seafood-based consistently showed higher higher associations with mortality. 

“We saw some association for sugar-sweetened beverage and artificially-sweetened beverages with a higher mortality,” Song told the Global Mail.

However, the ultra-processed foods umbrella is pretty large, but it should be noted for the Harvard study, alcohol was not included in the primary analysis because it is a well-studied risk factor for premature death.

The British Heart Foundation lists ice cream, ham, sausages, crisps, mass-produced bread, some breakfast cereals, biscuits, carbonated drinks, fruit-flavoured yoghurt, instant soups, and some alcoholic drinks as such.

Ultra-processed foods are known to be detrimental to our health.

Additionally, ultra-processed foods will also include additives, which make them non-perishable and give them extra flavour. Usually, these products are on the more affordable side.

Speaking to CNN, Song noted that while cereals and whole grain are considered to be ultra-processed foods, they contain beneficial nutrients.

But his advice is to either avoid or limit the consumption of processed foods.

• Eight everyday foods you might not realise are ultra processed – and how to spot them

Health risk associated with ultra-processed foods

Over the years there have been plenty of studies confirming that there are health risks associated with consuming heavily processed foods.

Such foods often contain a lot of saturated fat, added sugars and sodium, which lack nutrients and because they keep people full, one may not eat the nutrient-rich foods they should be eating.

Cancer Council NSW says while there is now well-established link between ultra-processed foods and cancer, eating large quantities could increase the cancer risk.

Ultra-processed foods can also lead to obesity, which increases the risk of developing 13 different cancers.

Additionally, the British Heart Foundation warns consuming a lot of ultra-processed foods can lead to an increased risk of high blood pressure, cardiovascular disease, heart attacks and strokes.

There have also been studies that suggest ultra-processed foods affects mental health.

A study from Deakin University found the risk of depression increases among people who consume a lot of ultra-processed foods.

Another study found that it only takes four weeks of a diet rich with ultra-processed foods to inflame the brain and elicit behavioural signs of memory loss.