Why We Might Never Know the Truth About Ultra-Processed Foods

An anonymous reader shares a report: A recent meeting of the American Society for Nutrition in Chicago was presented with an observational study of more than 500,000 people in the US. It found that those who ate the most UPFs (ultra-processed foods ) had a roughly 10% greater chance of dying early, even accounting for their body-mass index and overall quality of diet. In recent years, lots of other observational studies have shown a similar link - but that's not the same as proving that how food is processed causes health problems, or pinning down which aspect of those processes might be to blame.

So how could we get to the truth about ultra-processed food?

The kind of study needed to prove definitively that UPFs cause health problems would be extremely complex, suggests Dr Nerys Astbury, a senior researcher in diet and obesity at Oxford University. It would need to compare a large number of people on two diets -- one high in UPFs and one low in UPFs, but matched exactly for calorie and macronutrient content. This would be fiendishly difficult to actually do. Participants would need to be kept under lock and key so their food intake could be tightly managed. The study would also need to enrol people with similar diets as a starting point.

It would be extremely challenging logistically. And to counter the possibility that people who eat fewer UPFs might just have healthier lifestyles such as through taking more exercise or getting more sleep, the participants of the groups would need to have very similar habits. 'It would be expensive research, but you could see changes from the diets relatively quickly,' Dr Astbury says. Funding for this type of research could also be hard to come by. There might be accusations of conflicts of interest, since researchers motivated to run these kind of trials may have an idea of what they want the conclusions to be before they started.

Read more of this story at Slashdot.