The aim of this study is to examine the association between a low carbohydrate diet, quality of life and glycaemic control in Australian adults with T1DM. The first phase of the study will develop and validate a diabetes specific quality of life questionnaire for adults with T1DM. The second phase will undertake a low carbohydrate diet intervention and examine its association with quality of life and glycaemic control, pre and post the dietary intervention. The novel outcomes will include a new validated Australian T1DM specific quality of life questionnaire and an investigation as to whether a low carbohydrate diet mediates the relationship between quality of life and glycaemic control in Australian adults with T1DM.

Phase 1:

Aim: To develop a reliable and valid diabetes specific quality of life questionnaire for use in Australian adults living with type 1 diabetes mellitus (T1DM).

Objectives:

1. To develop a new Australian diabetes specific quality of life online questionnaire integrating participant feedback using a one to one interview method;
2. Pilot the study developed online questionnaire with adults that have type 1 diabetes mellitus and
3. Conduct factorial validation of the study developed online questionnaire using advanced statistical modelling techniques.

Phase 2:

Aim: The aim of this study is to examine the association between a low carbohydrate diet, quality of life and glycaemic control in adults living with T1DM.

Objectives:

1. To examine the association between quality of life and glycaemic control in adults with T1DM;
2. Implement a low carbohydrate diet in a cohort of adults living with T1DM;
3. Examine the association between a low carbohydrate diet and glycaemic control in adults with T1DM: pre and post intervention;
4. Examine the association between quality of life and a low carbohydrate in adults with T1DM: pre and post intervention and
5. Investigate whether a low carbohydrate diet mediates the relationship between quality of life and glycaemic control in adults with T1DM.

Inclusion Criteria:

• Male, female or unspecified gender;
• 18 years of age or over;
• Type 1 diabetes for ≥1 year from diagnosis date and
• Individuals who administer insulin using multiple daily injections.

Exclusion Criteria:

• Patients with type 2 diabetes mellitus;
• Patients with gestational diabetes mellitus;
• Presence of a known food allergy or intolerance that may affect the participants' health or adherence during the intervention;
• History of an eating disorder;
• BMI <25.0kg/m2 to 29.9kg/m2;
• Age <18 years;
• An active medical problem that may hinder the persons' ability to take part or potentially affect study outcomes e.g. a recent myocardial infarction, stroke or peripheral revascularisation (within 3 months), active treatment of diabetic retinopathy, recent serious infection (requiring in-hospital treatment or prolonged antibiotic therapy), active mental health complaint or other active medical problems determined by medical staff;
• Pregnancy or expectation of conceiving. Participants will be withdrawn at any stage from the study if pregnancy occurs;
• The use of medications that may affect body weight/body composition (including but not limited to phentermine and corticosteroids);
• Those for whom the written materials may be unsuitable such as vision impaired or illiterate individuals;
• Those unable to understand English;
• Those who failed to provide informed consent and
• Those who administer insulin using a continuous subcutaneous insulin infusion.

• Male, female or unspecified gender;
• 18 years of age or over;
• Type 1 diabetes for ≥1 year from diagnosis date and
• Individuals who administer insulin using multiple daily injections.

The data collected in this study is specific to this doctoral research project. Therefore, there will be no data sharing with any other researchers who are not members of this study. Where a current research team member wishes to use any of this data research purposes, the research must be approved by an Ethics committee, involve the PI who will ultimately retain oversight of all future uses of data and will remain the ongoing custody of data and/or research outputs.