Functional dyspepsia redefined: evidence supporting inflammatory dyspepsia - a systematic review

Area of Science:

• Gastroenterology
• Immunology
• Nutritional Science

Background:

• Functional dyspepsia (FD) is a prevalent gastrointestinal disorder marked by symptoms such as early satiety, postprandial fullness, and epigastric pain.
• Emerging evidence suggests a link between dietary antigens, inflammation, and the manifestation of FD symptoms.

Purpose of the Study:

• To systematically review existing evidence on the impact of dietary factors on the pathogenesis of functional dyspepsia (FD).

Main Methods:

• A comprehensive systematic search was performed across major scientific databases (MEDLINE, EMBASE, PsycINFO, Scopus, Cochrane) for studies published between January 2000 and December 2024.
• Studies involving adult participants diagnosed with FD according to Rome criteria were included. Data synthesis was conducted narratively, with rigorous risk of bias assessment using established tools (ROBIS, RoB 2.0, ROBINS-I).

Main Results:

• Fourteen studies were included, examining dietary factors such as FODMAPs/wheat, prebiotics/probiotics, capsaicin, essential oils, herbal therapies, and ginger.
• High-FODMAP foods, gluten, and capsaicin were associated with increased FD symptoms, potentially due to impaired epithelial barrier function, immune activation, or microbiota changes.
• Interventions including probiotics, peppermint-caraway oil, herbal formulations, and ginger demonstrated potential in alleviating symptoms through anti-inflammatory or microbiota-modulating mechanisms.

Conclusions:

• Specific dietary components can trigger inflammation and symptoms in FD patients.
• The study proposes renaming certain FD presentations to 'inflammatory dyspepsia' when gastrointestinal inflammation is evident.
• Further large-scale randomized trials are essential to validate these findings and establish precise dietary guidelines for FD management.