An international research project has revealed that genetic differences in carbohydrate-active enzymes in humans could influence the effectiveness of a carbohydrate-reduced diet for individuals with irritable bowel syndrome (IBS).
An international research project has revealed that genetic differences in carbohydrate-active enzymes in humans could influence the effectiveness of a carbohydrate-reduced diet for individuals with irritable bowel syndrome (IBS).
This research, published in Clinical Gastroenterology & Hepatology, indicates that IBS sufferers with genetic issues related to carbohydrate digestion tend to respond better to certain dietary changes. This discovery could facilitate personalized treatments for IBS, utilizing genetic markers to identify which patients are likely to benefit from specific diets.
The study was led by Professor Mauro D’Amato, Ikerbasque Research Professor at the Gastrointestinal Genetics Research group at CIC bioGUNE and the Department of Medicine and Surgery at LUM University in Italy. It also included contributions from researchers worldwide, part of the GenMalCarb consortium led by Dr. Maura Corsetti from the Nottingham Digestive Diseases Centre at the University of Nottingham. The consortium features experts from institutions in Germany (IKMB and University of Hannover) and Belgium (TARGID).
Irritable bowel syndrome (IBS) affects around 10% of people worldwide and is characterized by symptoms like abdominal discomfort, bloating, diarrhea, or constipation. Despite its high prevalence, finding effective treatments for IBS can be quite difficult due to the wide variation in symptoms and individual responses to dietary changes or medications.
Patients frequently associate their symptoms with certain foods, particularly carbohydrates, prompting the adoption of dietary restrictions or eliminations as a treatment method, although the effectiveness can vary for each individual.
The field of nutrigenetics, which studies how our genes and nutrition interact to impact health, has shown that genetic variations can influence our ability to digest certain foods. A familiar example is lactose intolerance, where an enzyme deficiency impairs the digestion of dairy products.
This innovative study proposes that variations in carbohydrate-active enzymes (hCAZymes) might similarly influence how patients with IBS react to a low-FODMAP (fermentable carbohydrates) diet.
The research team discovered that individuals possessing hypomorphic (defective) variants in their hCAZyme genes were more inclined to see improvements on a carbohydrate-reduced diet.
Involving 250 IBS patients, the study compared two interventions: a low-FODMAP diet and the medication otilonium bromide. Notably, among the 196 patients on the diet, those with defective hCAZyme genes showed substantial improvement compared to those without such variations. This effect was especially clear in patients with diarrhea-predominant IBS (IBS-D), who were six times more likely to benefit from the diet. Conversely, this genetic difference was not seen in patients on medication, emphasizing the role of genetics in dietary response.
“These results indicate that genetic variations in hCAZyme enzymes, crucial for carbohydrate digestion, could serve as essential markers for creating personalized dietary treatments for IBS,” says Dr. D’Amato. “Being able to predict which individuals will respond favorably to a carbohydrate-reduced diet could significantly enhance IBS management, leading to greater adherence and improvement in conditions.”
Looking ahead, integrating the understanding of hCAZyme genetics into medical practice could help healthcare providers identify which patients are likely to reap the most benefits from specific dietary plans. This not only prevents unnecessary restrictive diets for those who won’t benefit but also paves the way for personalized healthcare approaches in IBS.
“These findings require further validation through additional studies. If confirmed, this approach could lead to personalized dietary and treatment approaches,” adds Dr. Maura Corsetti.
