Our ultra-processed diets are causing weight gain and memory loss, research finds

We know that junk food is bad for us, but some processed foods decieve and could be harming our health

Child holding fries and soda
(Image credit: Getty Images)

Many of us know that the foods we eat affect our bodies. You've probably felt it after a substantial meal, with an overfull stomach and the sleepiness that often follows. The effects of a diet high in junk food are particularly stark, with this food group linked to weight gain and several long-term health conditions. 

It's always worth learning how to eat healthily, but new research has highlighted just how important this is. Two independent studies have shown that processed foods, even those which appear healthier, are increasingly common in our diets but contribute to weight gain and may even be causing memory loss. 

Researchers at the NYU School of Global Public Health explored how diets changed between the early 2000s and late 2010s in the US. Across the period, there was a 3.5% increase in how many calories people consumed from ultra-processed foods, those which industrially manufactured and ready-to-eat like microwave meals and convenience foods. 

A side effect of this is that, generally, people are eating fewer healthier whole foods, like fruits, veg, grains, legumes, and oats. The two trends combined may be why there's increasing evidence that ultra-processed foods contribute to many chronic health conditions. 

In a separate study, a team at Ohio State University found that diets high in processed foods caused inflammation in the brain, leading to some degree of memory loss. This effect was more pronounced among older populations compared to their younger counterparts.   

Person eating a ready meal

(Image credit: Getty Images)

It's a problematic finding as the NYU School of Global Public Health researchers saw that over-60s had the sharpest increase in ultra-processed foods in their diets over the past two decades. Although the Ohio State University research was performed on rats, a common stand-in for humans, the two studies seem to validate each other. 

Anecdotally, the study's observations seem realistic, as the older rats displayed a range of memory-related problems, including forgetting new spaces and a decreased fear response to danger. This is why Ruth Barrientos, one of the study's authors, believes the findings notable. 

She notes the research indicates that "consumption of a processed diet can produce significant and abrupt memory deficits – and in the aging population, rapid memory decline has a greater likelihood of progressing into neurodegenerative diseases such as Alzheimer's disease."

This isn't the first time Barrientos has explored the links between diet and brain inflammation, with her past research finding that docosahexaenoic acid (DHA) can reduce this inflammatory response. DHA is an omega-3 fatty acid commonly found in fish and other seafood. 

While you can get your recommended intake through seafood alone, it might be worth adding some of the best fish oil supplements into your diet as well. These are high in omega-3, which is known to lower cholesterol, blood pressure, and some forms of blood fat. 

James Frew
James Frew

James is a London-based journalist and Staff Writer at Fit&Well. He has over five years experience in fitness tech, including time spent as the Buyer’s Guide Editor and Staff Writer at technology publication MakeUseOf. In 2013 he was diagnosed with a chronic health condition, which spurred his interest in health, fitness, and lifestyle management.


In the years since, he has become a devoted meditator, experimented with workout styles and exercises, and used various gadgets to monitor his health. In recent times, James has been absorbed by the intersection between mental health, fitness, sustainability, and environmentalism. When not concerning himself with health and technology, James can be found excitedly checking out each week’s New Music Friday releases.