Effect of Prebiotics on the Gut Microbiome Profile and Beta Cell Function

Inclusion Criteria: * Be between 11-17 years of age * Willing to consume HAMS-AB and follow a diabetic diet * Diagnosed by American Diabetes Association criteria with T1D in the last 4-36 months * Random non-fasting C-peptide of 0.17nmol/ml or greater * Willing to use an effective form of contraception if sexually active * BMI\< 85% for age and sex * Positive for any one of the following diabetes-related autoantibodies that are tested clinically \[insulin autoantibody (if tested within 14 days of diagnosis), glutamic acid decarboxylase (GAD), insulinoma-associated protein-2 (IA-2), or Zinc transporter 8 autoantibodies (ZnT8)\]. Exclusion Criteria: 1. Presence of severe, active disease that interferes with dietary intake or requires the use of chronic medication, except for well-controlled hypothyroidism and mild asthma not requiring oral steroids. 2. Diabetes other than T1D (Known monogenic forms of diabetes, Type 2 diabetes) 3. Chronic illness known to affect glucose metabolism (e.g. Cushing syndrome, polycystic ovarian disorder, cystic fibrosis) or taking medications that affect glucose metabolism (e.g. steroids, metformin) 4. Psychiatric impairment or current use of anti-psychotic medication 5. Any condition that, in the investigator's opinion, may compromise study participation or may confound the interpretation of the study results. 6. Female participants of child-bearing age with reproductive potential, must not be pregnant and agree to use an effective form of birth control or be abstinent during the study period (see below) 7. History of recurrent infections 8. History of on-going infections or antibiotic treatment within the past three months 9. History of immune compromise 10. Steroid intake (inhaled or oral) 11. Other immunosuppressant use in past 6 months 12. History of gastrointestinal disease 13. Possible or confirmed celiac disease 14. Pregnancy or possible pregnancy 15. Allergy to corn (prebiotic) 16. Allergy to milk or milk products or soy present in Boost 17. Participation in other intervention research trials within the past 3 months 18. Anticipate major changes in diabetes management during study (change from injection to pump, new start of continuous glucose monitoring) 19. Consuming high fiber or vegetarian diet (consuming three or more servings of high fiber foods on 4 or more days per week) using validated dietary assessments (see below under schedule of events table). 20. Taking fiber supplements \-