Currently no consensus exists on the optimal way to manage asymptomatic patients with celiac disease (CD) and Type 1 diabetes (T1D). The impact of dietary treatment as it pertains to clinically relevant outcomes such as metabolic control, bone mineralization and wellbeing will be evaluated in this study. A randomized controlled study longitudinally evaluating HbA1c and glycemic excursions using continuous glucose monitoring will rigorously determine the impact of a gluten-free diet (GFD) on blood glucose variability in patients with T1D.

Inclusion Criteria:

Subjects must meet each of the following criteria for inclusion into the study:

1. Males and females age between 8 and 45 years.
2. Diagnosis of T1D by American Diabetes Association (ADA) criteria with duration of T1D greater than 1 year.
3. CD screen positive (Positive TTG serology).
4. Presence of a positive duodenal biopsy for CD (Marsh score of 2 or greater).
5. Ability of the subject or a legally authorized representative to speak and read English or French.
6. Ability of the subject to participate in all aspects of this clinical trial.
7. Written informed consent must be obtained and documented, with assent of the child if <14 years of age.

Exclusion Criteria:

1. Prior diagnosis of CD.

2. Symptoms or other evidence of overt CD defined by at least one of:

   • CD symptoms using the Gastrointestinal Symptom Scale [GISS]
   • Impaired growth
   • Anemia

3. Presence of recurrent apthous ulcers (painful mouth ulcers involving mucous membranes) or dermatitis herpetiformis (blistering skin rash). Mouth or skin lesions known to be related to diagnosed herpes are not included in this exclusion criteria.

4. Conditions which in the opinion of the investigator may interfere with the subject's ability to participate in the study.

5. Prior enrolment in the current study.

6. Concurrent enrolment in a longitudinal intervention study.

7. Previously diagnosed or treated osteoporosis.

8. Pregnancy or lactation.