Which foods have the most inflammatory effect on the digestive system?
The upper digestive tract (mouth, throat and stomach) is probably less apt to get irritated from compounds in food since what you’ve eaten isn’t yet broken down there. Hot sauce is an exception! Inflammation in these areas is likely due to bacteria or autoimmune responses. It’s rare that foods cause direct inflammation on the interior lining of the intestinal tract from within the gut itself. Usually it’s by way of immunoregulatory pathways and depends on the health of that lining.
When nutrition and medical experts speak of an inflammatory effect from food, they’re usually talking in reference to the two inflammatory bowel diseases (IBD) Crohn’s disease or ulcerative colitis. The causes may be genetic, environmental or both. It’s assumed a pathogenic agent – bacteria, viruses, antigens – triggers the body’s immune system to produce an inflammatory reaction in the digestive system. Certain types of foods may cause greater symptoms, but each person’s response varies.
Outside of IBD, maybe you’re referring to foods that cause other gastrointestinal problems like gas, bloating and pain such as from indigestion, reflux or irritable bowel syndrome? Here the list of problem foods can vary depending on the person’s tolerance. Lactose-containing milk products, nuts, legumes, fructans in grains and vegetables, sugar alcohols, heavy spices, caffeine, and greasy foods are the top contributors to gut issues.
Though you may want to avoid inflammatory foods, I’d suggest focusing on the positive by seeking foods that fight inflammation systemically. These include beneficial spices, broccoli, green leafy vegetables, potatoes, tomatoes, nuts, olive oil, fatty fish (such as salmon and mackerel), oysters, wheat germ, liver and citrus fruit.
- Inflammation in the intestinal tract: pathogenesis and treatment. Blumberg RS. Digestive Diseases 2009; 27(4): 455–464. doi:10.1159/000235851
- “Symptoms & Causes of Gas in the Digestive Tract.” National Institute of Diabetes and Digestive and Kidney Diseases, U.S. Department of Health and Human Services, 1 July 2016, www.niddk.nih.gov/health-information/digestive-diseases/gas-digestive-tract/symptoms-causes.
- Harvard Health Publishing. “Foods That Fight Inflammation.” Harvard Health, Harvard Medical School, June 2014, www.health.harvard.edu/staying-healthy/foods-that-fight-inflammation.
– Debbie J., MS, RD
This article should not replace any exercise program or restrictions, any dietary supplements or restrictions, or any other medical recommendations from your primary care physician. Before starting any exercise program or diet, make sure it is approved by your doctor.
Some questions have been edited for length and/or clarity.