
The Problem With Ultra-Processed Food
While many people understand the difference between unprocessed and processed foods, fewer recognise what sets processed foods apart from ultra-processed foods. The distinction lies in the degree of processing, the use of additives, and how artificial these food products have become.
Ultra-processed foods are heavily refined and filled with additives like preservatives, sweeteners, and artificial flavors, making them nutritionally inferior and potentially harmful to gut health.
Does this mean all processed foods are bad? No, some processed foods can fit into a healthy diet depending on your choices. However, UPFs should be avoided due to their poor nutritional quality and harmful effects. For instance, the British Medical Journal reports that UPFs make up 58% of the average American’s calorie intake and contribute nearly 90% of added sugar consumption, making them a significant driver of health problems (Steele 2010).
For optimal gut health as you age, cutting back on ultra-processed foods (UPFs) is crucial. Research consistently shows that diet significantly influences disease risk and our overall health by shaping our gut microbiome (Armet 2022).
By understanding the difference between processed foods and UPFs, it becomes clear why reducing UPFs is essential for long-term health. A Mediterranean-style diet, rich in fresh, whole foods and minimally processed options, offers a strong foundation for supporting the gut and overall well-being.
What Are Processed Foods?

According to the USDA, (United States Department of Agriculture) processed foods are foods that have undergone changes from their natural state. When we talk about “changes”, it may simply include washing freshly grown produce, as an example let’s say potatoes. This implies a bag of potatoes from your local grocery store would become a “processed food”. But if those potatoes are deep-fried and become French fries, they become highly-processed.
Processed foods are any food products that have undergone a change from their original state. These changes can include washing, cutting, freezing, cooking, or packaging to make food more convenient or preserve it longer (Harvard T.H. Chan). It is important to remember the word “processed food” is a very broad term, and includes any raw agricultural commodity even including grains, seeds, nuts, fruits and vegetables.
Examples include canned vegetables, frozen fruits, whole-grain bread, and pasteurised milk. These minimally processed foods often retain much of their nutritional value and are generally considered healthy.
In contrast, ultra-processed foods (UPFs) go through extensive industrial processes and often include added sugars, unhealthy fats, salts, preservatives, and artificial ingredients. Examples of UPFs include soft drinks, packaged snacks, instant noodles, and ready-made meals.
While convenient and often tasty, these foods are linked to adverse health outcomes such as obesity, cardiovascular disease, and diabetes. They often lack fibre, micronutrients, and bioactive compounds while being calorie-dense and nutrient-poor.
Examples of Processed Foods
These foods undergo basic preparation methods to improve shelf life, safety, or convenience while retaining their natural form and nutritional quality. Processed foods vary widely in their level of processing and nutritional value. Understanding the differences between minimally processed and highly processed foods is essential for making informed dietary choices.
Examples include:
These foods are often considered healthy and form the foundation of many balanced diets, including the Mediterranean diet. Other minimally processed foods not listed include canned tomatoes and beans.
Take-Aways
Articles of Interest
What Are Ultra-Processed Foods?

Almost all foods we consume undergo some level of processing, but not all processed foods are created equal. The key lies in the degree of processing.
For example, roasting potatoes or grilling chicken (minimally processed) retains much of the food’s natural quality, while deep-fried French fries and chicken nuggets with flavoured seasonings (ultra-processed) are far removed from their original state.
Similarly, raw nuts are a healthy snack (minimally processed), but honey-coated roasted peanuts with artificial additives are considered ultra-processed.
Minimally processed foods often undergo light processing such as washing, chopping, freezing, or canning without losing their core nutritional value. In contrast, ultra-processed foods are highly modified, often incorporating artificial flavours, sweeteners, colours, preservatives, and emulsifiers that dramatically alter their composition.
Minimising ultra-processed food intake can have significant health benefits, as these foods are linked to obesity, cardiovascular diseases, diabetes, and other chronic conditions.
Natural Sugars Don’t Pose A Health Threat
Do certain sugar varieties offer better health benefits? According to Harvard Health Publishing, unlike refined white sugar, consuming natural sugars found in foods like fruits is not associated with adverse health effects for most people. This is because the sugar content is typically modest and comes “packaged” with fibre and other beneficial nutrients. Our bodies don’t require nor gain benefits from the consumption of any added sugars. To prevent these health concerns, replace refined man-made sugars with healthier, more natural alternatives. (Ashwell 2015)
According to a study in the British Medical Journal, ultra-processed foods account for 58% of the calories consumed in the United States and contribute nearly 90% of added sugar intake (Steele et al., 2016).
Characteristics of Ultra-Processed Foods
Examples of Ultra-Processed Foods
Why Avoid UPFs In Your Diet?

Researchers speculate that long-term or permanent exposure of our gut microbiota to even low levels of modern food additives may modify the composition and function of our gut microbiota, and thus influence our immune system.
By focusing on minimally processed or whole foods such as fresh fruits, vegetables, nuts, seeds, whole grains, and lean proteins, we can build a diet that promotes long-term health while avoiding the pitfalls of highly processed diets. Let’s now look at 3 key studies that explain why consuming UPF foods regularly long-term is unsafe:
3 Key Studies Show UPF Consumption Harm
Key Mechanisms of UPF Harm
The growing body of research on ultra-processed foods (UPFs) reveals several mechanisms by which they negatively impact our health.
Here’s why it’s crucial to reduce or eliminate UPFs from our diet:
Let’s look at a few relevant studies on UPFs and health:
Convenient, Affordable, and Highly Addictive

Many people continue consuming ultra-processed foods (UPFs) due to their convenience, affordability, and highly addictive qualities, despite their lack of health benefits. These foods are designed to be easy, tasty, and ready-to-eat, which appeals to busy lifestyles. However, they can significantly harm our health over time.
Once people eliminate highly processed foods from their diet for several weeks or months, their cravings for these products often fade. This shift occurs as the gut microbiome becomes healthier and more balanced, promoting beneficial bacterial colonies. These bacteria thrive on real, nutrient-dense foods rather than artificial additives and refined ingredients.
As a result, many people lose the taste for highly-processed foods and feel physically uncomfortable if they attempt to return to their old eating habits, such as indulging in chips or chicken nuggets with dips. This discomfort can include bloating, sluggishness, or feeling mentally unwell.
Over time, continued reliance on UPFs negatively affects both our mental and physical health. Studies show that such diets can impair cognitive function, increase anxiety and depression, and promote chronic diseases like obesity and diabetes.
Moreover, UPFs contribute to gut dysbiosis, fostering harmful microbes while suppressing beneficial ones, leading to long-term damage to digestion, immune function, and overall well-being. Cutting out UPFs not only helps reverse these effects but also restores the body’s natural ability to crave and thrive on whole, nutrient-dense foods.
Ultra-Processed Foods as Addictive Substances

Ultra-processed foods (UPFs) are deliberately engineered for maximum taste, texture, and shelf life. They are loaded with industrial-grade chemicals, artificial additives, and flavour enhancers that are not typically found in home kitchens. These foods often include artificial sugars, unhealthy fats, preservatives, stabilisers, and agents to modify texture, colour, and flavour. Their design is highly intentional—to be irresistible and, for some, addictive.
Recent studies argue that UPFs meet criteria to be classified as addictive substances, similar to tobacco products. They are described as “industrially mass-produced and sensory-enhanced edible substances” rather than actual foods because they bear little resemblance to whole, unprocessed items (McManus 2020).
The addictive potential of UPFs, combined with their low cost and heavy marketing, contributes significantly to global health issues like obesity, diabetes, and heart disease. One review called UPFs “toxic and ready for regulation,” urging significant sugar reduction as a necessary measure for public health (Lustig 2020).
The addictive nature of UPFs lies in their engineering. Scientists and food psychologists craft these foods to trigger the brain’s reward system through enhanced taste, smell, and texture. This makes them difficult to stop eating and leads to overconsumption of calories. Research highlights how this addiction to UPFs is a major factor driving the high public health costs associated with obesity and diet-related diseases. Their design ensures they are not only palatable but habit-forming, perpetuating a cycle of dependency (Gearhardt 2022)
The evidence underscores that breaking away from UPFs is essential for better health. Their addictive characteristics, combined with low nutritional value and potential to drive chronic illnesses, make them a critical focus in improving diet quality worldwide.
Ultra-Processed Foods and Gut Health

An increasing body of research shows that ultra-processed foods (UPFs), which are typically high in sugar, unhealthy fats, and artificial additives, can negatively impact the gut microbiome.
These foods are manufactured in ways that disrupt the balance of trillions of bacteria in the intestines, promoting the growth of harmful microorganisms. This imbalance, known as dysbiosis, is linked to a range of chronic diseases, including inflammatory bowel disease and irritable bowel syndrome. (Madhogaria 2022)
Refined sugars and additives in UPFs feed harmful bacteria and fungi in the gut, including Candida, which can lead to inflammation and other digestive issues. A study demonstrated that diets rich in refined sugars can disrupt the gut microbiota, contributing to poor health through various mechanisms, including the promotion of chronic diseases and weight gain (Satokari 2020). The symptoms of dysbiosis are often ignored but are key signals from the gut microbiota.
Common dysbiosis signs include:
Key Takeaways
Ultra Processed Foods Linked With Poor Mental Health

Historically, mental health and nutrition were closely linked, but the rise of pharmaceutical treatments in the 20th century shifted focus away from diet-based interventions.
However, recent research highlights how diets rich in ultra-processed foods can negatively impact mood, cognition, and overall mental well-being. A study demonstrated a clear association between UPF consumption and an increased risk of depression, emphasising the importance of considering the “non-nutritional aspects” of diet for mental health (Adjibade 2019).
Ultra-processed foods create a poor gut environment, which is now understood to influence brain health through the gut-brain axis. This connection between gut health and mental function reveals how poor diets contribute to systemic inflammation and oxidative stress, conditions linked to neurodegenerative diseases like Alzheimer’s and Parkinson’s, as well as mood disorders like anxiety and depression. (Leo 2020).
Emerging research also links nutrition to societal issues such as rising rates of violence and aggression. Nutritional deficiencies associated with high-UPF diets may exacerbate mental health challenges, hinting at the potential for diet-focused public health strategies to mitigate these crises (Kaplan 2022).
Key Takeaways
Rethinking Our Diet in Favour of a Healthy Microbiome

Are your food choices influenced by marketing? A study involving nearly 90,000 supermarket food advertisements found that 45.7% promoted ultra-processed foods (UPFs), while only 5.1% featured minimally or unprocessed foods.
This shows how advertising skews consumer choices toward unhealthy options. UPFs may smell and taste good, but remember—they’re designed to be addictive and appealing, often at the expense of your health (Zhong 2022).
The health impacts of UPFs are well-documented. A systematic review of 43 studies identified a strong link between UPF consumption and various diseases, including obesity, type 2 diabetes, cancer, cardiovascular diseases, depression, and even increased all-cause mortality. Remarkably, no studies reported positive health outcomes associated with UPFs (Elizabeth 2020).
Our gut microbiome, a critical component of overall health, is particularly vulnerable to the negative effects of UPFs. The microbiome is often described as the “black box” of nutritional research due to its complexity and significant influence on our well-being.
UPFs disrupt the balance of beneficial bacteria, while whole foods support a thriving gut microbiome, improving digestion, immunity, and mental health. Shifting away from UPFs to a whole foods-based diet is key to nurturing this intricate system.
Conclusion: The Risks of Ultra-Processed Foods
While both processed and ultra-processed foods involve some level of preparation, UPFs are far more detrimental to health. They are extensively modified, often containing artificial additives and sugars that disrupt the gut microbiome, contribute to chronic disease, and promote overeating.
That’s why I recommend the Foundation diet—focused on whole, raw, and minimally processed foods—as a healthier long-term choice. Reducing UPF intake can help improve overall health and prevent chronic diseases associated with diet.
How You Limit UPFs In Your Life
Here are some of my favourite tips and and effective strategies to help limit processed foods in our family’s diet allowing us to make healthier choices that support our microbiome. I’d like you try following many, if not most of these points. You’ll build better gut health and feel amazing!

Home Grown Is Always Best
We often choose UPFs just for their convenience. By growing some of our own food, we become less reliant on pre-packaged and ultra-processed food, encouraging the preparation of home-cooked meals using whole ingredients.
We also know where our food comes from, a connection that can lead to a greater appreciation for healthy whole foods. When we grow our own food, we are encouraged to eat more seasonally, consuming produce when it’s at its freshest and most nutritious. Homegrown fruits and vegetables typically have higher fibre content as well.
I hope this article has inspired you towards taking steps in eliminating UPFs from your diet, and instead – choosing fresh, whole foods. Thank you for reading this page, please leave a comment with your views on ultra-processed foods.

Eric Bakker N.D.
Greetings! I am a naturopathic physician from New Zealand. Although I’ve retired from clinical practice since 2019, I remain passionate about helping people improve their lives. You’ll find I’m active online with a focus on natural health and wellbeing education through my Facebook page and YouTube channel, including this website.