Systemic Sclerosis DIet for GastrointESTinal Symptoms

The rationale for keeping the diets (arms/interventions names) vague is it prevents other researchers from using these diets in their studies, minimizes expectation bias of patients (who can have preference for one diet over other) and prevents participants from trying other diets before end of study period in case they don't respond.

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