GPT and irritable bowel syndrome: A regression analysis of the IBS cohort showed no significant relationship between 25(OH)D and ESR (R2 = 0.03, β = -0.05, p = 0.31), ALT (R2 = 0.043, β = 0.006, p = 0.94) and albumin (R2 = 0.046, β = 0.057, p = 0.92) after adjusting for age, gender, race, season, and BMI SDS.