We’ve known for some time that eating a diet high in ultra-processed foods can negatively affect our health. Research has linked these foods to weight gain, cardiovascular disease, and other chronic health conditions. Now, emerging research suggests that our brains may be affected, too.

A recent CBC News article reports on a study co-authored by researchers at McMaster University that examined the diets and brain MRI scans of more than 8,700 Canadian adults. The researchers found that people who consumed more ultra-processed foods were more likely to have brain changes associated with an increased risk of stroke, dementia, and cognitive decline.

These findings are concerning, although it’s important to note that the study identified an association rather than proving that ultra-processed foods directly cause these changes. More research is needed to understand the relationship and whether dietary changes can help protect brain health over time.

Still, I think it’s another good reason to pay attention to what we put on our plates.

What exactly are ultra-processed foods?

Ultra-processed foods are generally industrially manufactured products made largely from refined ingredients and substances, often with added flavours, colours, preservatives, and other additives. Many are designed to be convenient, inexpensive, and appealing, but they often contain less fibre and fewer beneficial nutrients than whole or minimally processed foods.

Think packaged snack cakes, sugary breakfast cereals, instant noodles, and many fast-food items.

But here’s an important distinction: not all processed foods are unhealthy. Canned beans, frozen vegetables, plain canned tomatoes and whole-grain oats are all examples of convenient foods that can make healthy eating easier. Processing can help preserve food, reduce waste, and make nutritious ingredients more accessible.

The goal isn’t to avoid every packaged food. It’s to make whole or minimally processed foods the foundation of our diets.

“Eat foods that rot, not rotten food”

This quote made me smile. It’s a memorable way of reminding us that real food doesn’t need a long list of ingredients to nourish us.

Vegetables, fruit, beans, lentils, whole grains, nuts, and seeds provide fibre, vitamins, minerals, and other beneficial compounds that support our health. A diet built around these foods can benefit far more than digestion alone. It can support cardiovascular health, metabolic health, and, potentially, long-term brain health.

Of course, fresh food doesn’t always last long, and nobody wants to waste good food. Frozen berries and vegetables, dried lentils, canned beans, and frozen homemade meals are all useful options. What matters most is the quality of the foods we eat overall, not whether everything comes fresh from the produce aisle.

Here are a few simple ways to get started:

• Cook more meals at home. Even a few simple meals each week can help you rely less on packaged convenience foods.
• Keep nutritious staples on hand. Canned beans, frozen vegetables, oats, brown rice, and lentils make it easier to pull together a meal when time is short.
• Build meals around whole plant foods. Add vegetables, beans or lentils, and whole grains to your regular meals.
• Make your own snacks and treats when practical. Homemade hummus, roasted chickpeas, fruit and oat-based treats can be satisfying alternatives to some packaged snacks.
• Take a gradual approach. You don’t have to overhaul your entire diet overnight. Start with one meal or food swap that feels manageable.

Healthy eating shouldn’t be a privilege

There is another point in this article that I think deserves more attention: individual choices are only part of the picture.

As the researchers point out, the cost of food, time available for meal preparation, and access to nutrition information can all influence what people eat. It’s easy to tell someone to cook more meals from scratch, but that advice doesn’t go very far if fresh ingredients are unaffordable, cooking facilities are limited, or someone is working multiple jobs.

Governments have a role to play in making healthier choices more accessible. That could include improving food labelling, making nutritious foods more affordable, strengthening nutrition education, and creating policies that encourage a healthier food environment.

People deserve clear information about the foods they’re buying, along with realistic opportunities to make nutritious choices. We shouldn’t place the entire responsibility for better health on individuals while ignoring the circumstances in which they live.

Feeding our brains as well as our guts

As a holistic nutritionist, I often talk about the connection between what we eat and how we feel. Food affects far more than our digestive systems, and this research is a reminder that our eating patterns may have implications for our health throughout our lives.

We still have more to learn about ultra-processed foods and brain health, but we don’t need to wait for every question to be answered before taking practical steps toward a healthier diet.

Eating more whole plant foods, preparing simple meals and keeping nutritious staples within reach are good places to start. And as a society, we can work toward making those choices easier for everyone.

Eat foods that rot, not rotten food. It’s a quote worth remembering!