Researchers from an Irish university in Cork have identified that dietary patterns high in fried meats, fast foods, sugary drinks, and full fat dairy can raise the risk of inflammatory bowel disease and colorectal cancer, according to a review published in Nature Reviews Microbiology.
To clarify which eating patterns are most beneficial or detrimental for gut health, the team conducted a broad review of previously published studies on related dietary topics. The aim was to synthesize known effects of popular diet plans on the digestive system and immune responses.
The analysis considered six distinct diet types: the Mediterranean diet, emphasizing plant foods and healthy fats from fish, nuts, and olive oil; a high fiber diet that increases the share of dietary fiber; a plant based diet; a high protein approach; a ketogenic plan that markedly reduces carbohydrate intake in favor of fats; and the Western diet characterized by heavy consumption of fast foods, sweets, processed meats, and dairy products.
Findings indicated that adherence to a Western style diet correlated with higher instances of inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease, as well as colorectal cancer. The researchers noted that the main harmful components of this diet are saturated fats and added sugars, which can disrupt gut ecology and inflammatory processes.
When fiber is scarce, the intestines struggle to produce short chain fatty acids, molecules that play a key role in regulating immune function, energy metabolism, and inflammatory responses throughout the body. A lack of these nutrients can compromise gut health and beyond, affecting overall well being.
Earlier work in the field has explored the broader relationship between ancient viral elements and certain cancers, suggesting long term interactions between viral exposure, genetic regulation, and disease risk. The current synthesis adds to that conversation by highlighting how contemporary dietary choices shape gut health and cancer risk profiles in modern populations.