Systemic Sclerosis DIet for GastrointESTinal Symptoms

Inclusion Criteria: * Diagnosis of systemic sclerosis (SSc) as per ACR/EULAR classification criteria .• Self-reported moderate to severe gastrointestinal bloating or distension, with a UCLA SCTC-GIT 2.0 bloating Scale score ≥2.00 on (0.00-3.00 scale) at screening. * Willingness and ability to comply with dietary intervention and study procedures. * Ability to provide informed consent. Exclusion Criteria: * Diagnosis of inflammatory bowel disease (Crohn's disease or ulcerative colitis) or celiac disease. * Use of systemic antibiotics within 4 weeks prior to baseline. * History of gastrointestinal surgery (other than cholecystectomy or appendectomy unless in the last 3 months). * Severe cognitive impairment or psychiatric illness that would limit ability to follow dietary instructions. * Known allergy or intolerance to major components of any of the study diets (e.g., lactose, gluten) unless manageable within diet framework. * Current or recent (within 3 months) dietary intervention for managing GI symptoms (e.g. gluten-free diet, low FODMAP diet, etc.). * Clinically significant self-reported (≥10 percent weight loss) in the last 3 months * BMI less than 20 * Ongoing tube feeds or TPN * Participating in another interventional trial * Pregnancy or lactation, or planning pregnancy in the next 6 months