Do ultra-processed foods reduce inflammation? The short answer is no.
The idea that ultra-processed foods (UPFs) could reduce inflammation enough to affect disease risk is not supported by the current evidence. In fact, the opposite is true. A large review of the research concluded that high UPF consumption is linked to low-grade inflammation, which is a known driver of many chronic diseases [6]. This means that rather than helping, these foods are likely contributing to the very inflammation that increases your risk of conditions like heart disease, diabetes, and inflammatory bowel disease.
The evidence is consistent and comes from different angles. For instance, a study measuring specific proteins in the blood found that people who ate more UPFs had higher levels of several inflammatory markers, including interleukin-18 and tumor necrosis factor receptors [2]. Another study showed that UPF consumption was linked to higher white blood cell counts, which is a general sign of inflammation in the body [7]. These findings directly contradict the idea that UPFs could have an anti-inflammatory effect.
How does this inflammation translate into a higher risk of disease?
The link between UPFs, inflammation, and disease risk is strong and has been shown for several major health conditions. A large European study of over 266,000 people found that for every extra 260 grams (about one serving) of UPFs consumed daily, the risk of developing a combination of cancer, heart disease, and type 2 diabetes increased by 9% [1]. This suggests that the inflammatory effects of UPFs can accumulate and contribute to multiple diseases at once.
The connection is particularly clear for inflammatory bowel disease (IBD). A global study across 21 countries found that people who ate five or more servings of UPFs per day had an 82% higher risk of developing IBD compared to those who ate less than one serving per day [3]. Furthermore, a study of people already living with ulcerative colitis (a type of IBD) found that those who ate the most UPFs had significantly more episodes of active intestinal inflammation [4]. This shows that UPFs don't just increase the risk of developing a disease; they can also worsen inflammation in people who already have one.
What is it about ultra-processed foods that causes this harm?
It's not just one thing, but a combination of factors that make UPFs inflammatory. These foods are typically high in unhealthy fats, sugar, and salt, and low in fiber and beneficial nutrients. However, the problem goes beyond just their nutritional profile. A review of the evidence highlights that food additives common in UPFs, such as certain emulsifiers and sweeteners, can directly harm gut health by disrupting the gut microbiome and increasing intestinal permeability (often called 'leaky gut'), which triggers inflammation [5].
This is why simply counting calories or fat grams isn't enough. The unique combination of ingredients and industrial processing in UPFs appears to have a specific effect on the body's inflammatory pathways. For example, the study that looked at blood proteins found that UPF intake was linked to proteins involved in immune signaling and cell stress, which are key processes in the development of chronic inflammation [2]. This helps explain why the link between UPFs and disease is so consistent across different studies and populations.
About These Sources
This answer is built on 7 peer-reviewed studies — published from 2021 to 2024, 2 from 2024 or later, 7 in Q1 journals, collectively cited 996 times — selected as the most relevant from 7 studies that passed quality screening, drawn from 37 papers retrieved from a database of over 500 million.
Sources used in this answer
Consumption of ultra-processed foods and risk of multimorbidity of cancer and cardiometabolic diseases: a multinational cohort study
In a large European cohort of 266,666 people, each 260g/day increase in UPF consumption was associated with a 9% higher risk of developing multiple chronic diseases (cancer, cardiovascular disease, and type 2 diabetes) [1].
Associations of ultra-processed food consumption, circulating protein biomarkers, and risk of cardiovascular disease
In a Swedish cohort of 26,369 people, those with the highest UPF intake had an 18% higher risk of cardiovascular disease, and UPF intake was linked to higher levels of several inflammatory proteins in the blood [2].
Association of ultra-processed food intake with risk of inflammatory bowel disease: prospective cohort study
In a global study of 116,087 adults across 21 countries, eating 5 or more servings of UPFs per day was associated with an 82% higher risk of developing inflammatory bowel disease compared to less than 1 serving per day [3].
Ultra-Processed Food, Disease Activity, and Inflammation in Ulcerative Colitis: The Manitoba Living With IBD Study
Among 135 people with IBD, those with ulcerative colitis who ate the most UPFs had significantly more episodes of active disease and intestinal inflammation compared to those who ate the least [4].
Ultra-processed foods and food additives in gut health and disease
A review of the evidence found that food additives in UPFs, such as emulsifiers and sweeteners, can harm gut health by disrupting the gut microbiome and increasing intestinal inflammation [5].
Low-Grade Inflammation and Ultra-Processed Foods Consumption: A Review
A review concluded that high UPF consumption is linked to low-grade inflammation, which is a known risk factor for the development of chronic noncommunicable diseases [6].
Consumption of ultra-processed foods is associated with depression, mesocorticolimbic volume, and inflammation
In a study of 152 adults, higher UPF consumption was associated with more depressive symptoms, and this link was partially explained by higher white blood cell counts, a marker of inflammation [7].