Skip to content

One Major Side Effect of Eating Too Many Processed Foods, Says New Study

It might be time to cut back on the packaged cookies and yes, even the charcuterie boards..
FACT CHECKED BY Cheyenne Buckingham

It's no secret that fresh groceries leave your body feeling better than processed foods. Highly processed diets can sap your energy, hurt your skincare regimen, and even put you in a bad mood. Now, researchers have discovered yet another reason to cut out the Big Macs for good—turns out, diets full of processed foods can weaken your immune system and increase your risk of certain chronic diseases such as type 2 diabetes.

A recent study published in the journal PLOS Pathogens found that a Western-style diet—described as a diet rich in processed foods that are high in fat and refined sugars but low in fiber—could create a breeding ground for harmful gut bacteria and make you more susceptible to insulin resistance which can lead to type 2 diabetes. (Related: The 7 Healthiest Foods to Eat Right Now)

"Processed foods, such as high sugar foods and pre-packaged foods, lack fiber and nutrients which are needed to support the gut microbiota," Jonathan Valdez, RDN, CDCES, owner of Genki Nutrition, and Media Spokesperson for New York State Academy of Nutrition and Dietetics, said in an interview with Eat This, Not That!

"Studies have concluded that processed foods reduce the number of gut microbiota and influence the immune system's 'readiness' and the body's defense against pathogenic bacteria."

In other words, if your diet includes too many processed foods, you could be reducing the healthy bacteria in your gut that protect you from harmful bacteria that can a) make you sick immediately (think foodborne illness) and b) alter your gut microbiota and increase your risk of chronic inflammatory diseases in the long run.

So, what foods should you avoid to keep your gut health in tip-top shape? Abbey Sharp, a registered dietitian at Abbey's Kitchen, strongly recommends cutting back on red meat varieties that are high in preservatives, salt, and saturated fat including bacon, pepperoni, and hot dogs.

"While I don't believe in completely removing any one food from your diet, I think there's value in trying to limit our intake of ultra-processed foods," she said, adding that it's not just inflammatory infections and foodborne illnesses that you should be watching out for.

"We do have evidence to suggest that a diet rich in ultra-processed red meat like hot dogs may increase the risk of cancer. Even 'nitrate free' or 'natural' hot dogs contain natural nitrates so I suggest limiting consumption to special occasions."

Looking for foods that won't leave you at high risk? Try these 15 Homemade Swaps for Ultra-Processed Foods.

Clara Olshansky
Clara Olshansky (they/she) is a Brooklyn-based writer and comic whose web content has appeared in Food & Wine, Harper’s Magazine, Men's Health, and Reductress. Read more about Clara
Filed Under