Effect of Isoflavone and Vitamin D Supplementation on Serum Vitamin D Levels, Body Composition, Inflammatory Markers, and Quality of Life in Patients With Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic immune-mediated disorder characterized by recurrent intestinal inflammation, impaired nutritional status, and reduced quality of life. Nutritional deficiencies and alterations in body composition are frequently observed in patients with IBD and may contribute to disease burden and long-term complications. Isoflavones derived from fermented soy products, such as tempeh, have demonstrated anti-inflammatory properties in both experimental and clinical studies. Vitamin D is an important immunomodulatory nutrient, and its deficiency is common in patients with IBD. However, evidence regarding the combined effects of isoflavone and vitamin D supplementation on inflammatory markers, nutritional status, and quality of life in patients with IBD remains limited. This study aimed to evaluate the effects of daily tempeh powder supplementation providing approximately 50 mg of isoflavones and 4000 IU of vitamin D3 for 8 weeks in patients with IBD. Outcomes include changes in serum vitamin D concentration, body composition parameters, serum tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), and quality of life assessed using the Inflammatory Bowel Disease Questionnaire-9 (IBDQ-9).

Inclusion Criteria: * Male or female adults aged ≥18 years, diagnosed with inflammatory bowel disease including ulcerative colitis or Crohn's disease, receiving standard medical therapy for IBD, willing to provide written informed consent Exclusion Criteria: * Vegetarian, diagnosed as unclassifed IBD, patient with severe clinical manifestation requiring immediate medical management, with other diagnosed gastrointestinal diseases, pregnancy or lactation, severe hepatic impairment, with implant, with amputation of at least one extremity, with active infectious skin wounds or lesions.