A Harvard processed foods expert shares 3 simple food swaps you can make for a healthier brain and gut

• A researcher who studies processed foods said the work prompted him to make his own diet healthier.
• He cut back on certain foods after finding a link to health risks.

Once, chicken nuggets were a convenient, popular dinner option for Dr. W. Taylor Kimberly and his family.

But after studying ultra-processed foods in more detail, and seeing how they affect the brain, he's switched to grilled chicken instead.

Kimberly, a professor of neurology at Harvard Medical School and a neurologist at Massachusetts General Hospital, is the senior author of a new study linking ultra-processed foods to health risks like dementia and stroke.

"Since we began this study, I've paid more attention to what I eat," he told Business Insider. "But I'll be honest, there are many I enjoy, and I haven't eliminated them all."

While it's not news that ultra-processed foods are linked to poor health, the latest study helps us understand not just which foods might be healthy or unhealthy but how to make small, healthy changes without cutting them out entirely.

"Ultra-processed foods are such a big part of our diet. They're convenient and easy. There hasn't been as much work on thinking about not just the type of food but also how it's processed," he said.

The findings, published June 11 in the journal Neurology, are a step closer to helping scientists understand why processed food might be bad for our health. The study was observational, which means it can't directly tell us if processed food caused the health risks.

But it does offer hints at simple ways to make healthier choices, according to Kimberly, who offered tips on picking more nutritious snacks and how much processed food you should aim to cut back on.

Swapping out as little as two servings of processed food a week can help

When Kimberly and his team embarked on their study, their goal was to come up with some actionable advice for people. Is it possible to slightly reduce processed foods — without eliminating them entirely — and meaningfully improve your health?

Their research suggested you can.

Their study found that a 10% increase in processed food consumption was linked to a higher risk of cognitive impairment.

That's the equivalent of about two meals per week. The research team based their analysis on that amount because it felt like a realistic amount for people to reduce, and an easy goal to remember.

"The answer we came up with is that we move the needle, and we can take a lot of optimism from that," Kimberly said.

"Diet is really hard to change. There are many reasons we eat what we eat, such as time, convenience, and budget. All of these things impact the dietary choices we make," he said.

Choose whole foods high-fiber options like nuts and seeds

Years of research tell us that processed foods are harmful in part because they're often lacking in fiber and protein, as well as vitamins and minerals. They also introduce unhealthy ingredients into your diet, such as added oil, sugar, salt, and preservatives.

That means you can't offset the consequences of a junk food diet by popping some multivitamins or gulping a green juice afterward.

"If you're not eating a healthy meal, you're also eating an unhealthy meal, so the evidence suggests you can't just add a supplement. It's both sides that are important when thinking about brain health," Kimberly said.

The good news is that replacing highly processed foods with healthier alternatives can give you double the benefits because you're adding nutrients and cutting out potentially harmful additives at the same time.

For example, swapping French fries for baked sweet potatoes helps to reduce salt and oil in your diet but also brings in more vitamins and minerals.

Kimberly's research has inspired him to snack on nuts or carrots instead of cookies or crackers — cutting his sugar intake and quickly increasing the amount of fiber in his diet.

"We're not just feeding ourselves when we eat. We're feeding a really complicated ecosystem in the gut that helps metabolize what we eat," Kimberly said.

Aim for ingredients you recognize

You don't have to give up processed foods completely to improve your health. When you're reaching for something cheap and convenient, it can help to choose healthier processed food options that have recognizable ingredients, according to Kimberly.

"If you look at it and think, that could be made in my kitchen, that's a good indicator," he said.

In the long run, it can be more helpful to make a few small swaps you can stick to than trying (and failing) to swear off processed foods forever.

"In a perfect world, we would all eat unprocessed foods, but that's not reality," Kimberly said. "It's not a sprint. Short, big changes aren't the goal. Even modest changes, if they're sustainable, can matter."