What Or When to Eat to Reduce the Risk of Type 2 Diabetes (WOW)

Inclusion Criteria:

• Study participants will be aged 35 to 70 years, overweight or obese (BMI: >25 but <45 kg/m2), ≥15 on the AUSDRISK assessment tool and have HbA1c <6.5% at screening

Exclusion Criteria:

Type 1 or type 2 diabetes, or diabetes detected at screening HbA1c ≥6.5% (48 mmol/mol).

• A personal history/diagnosis (self-reported) of:

• major psychiatric disorders (schizophrenia, major depressive disorder, bipolardisorder, eating disorders)

• gastrointestinal disorders/disease (including malabsorption)

• haematological disorders (i.e. thalassemia, iron-deficiency anaemia)

• insomnia

• currently receiving, or have received treatment/diagnosis of cancer in the past 3 years (excluding non-melanoma skin cancer)

• significant liver or kidney disease

• previous or planned gastro-intestinal surgery (including bariatric surgery)

• Congestive heart failure (NYHA stage 2 or above)

• Previous myocardial infarction or significant cardiac event ≤ 6 months prior toscreening

• Previous cerebrovascular event ≤ 12 months prior to screening

and/or any other condition deemed unstable by the study physician.

Currently taking the following medications:

• any medication used, or known to lower blood glucose, or antidiabetic medications,including, but not limited to: SGLT2 inhibitors, metformin, sulfonylureas,glucagon-like peptide-1 (GLP-1) analogues [i.e. exenatide], thiazolidinediones orDPP-IV inhibitors [i.e. 'gliptins'])

• Medications affecting weight, appetite or gut motility, including, but not limitedto: (domperidone, cisapride, orlistat, phentermine, topiramate).

• Diuretics (i.e. frusemide, thiazides) or combination blood pressure medicationscontaining a diuretic

• Beta-blockers

• Glucocorticoids

• Anti-epileptic medications

• Antipsychotic medications

• Opioid medications unless combined with paracetamol in a single formulation and usedoccasionally on a PRN basis

Additional exclusion criteria include:

• do not consume a regular breakfast (i.e. eat breakfast on an average of 5 or moredays per week), and do not eat for more than 12 hours per day on an average of 5 ormore days per week

• have an extreme or restricted pattern of eating (i.e. following an intermittentfasting diet) or are already engaged in a TRE protocol

• shift-workers

• pregnant, planning a pregnancy or currently breastfeeding

• those who have lost or gained >5% of body weight in the last 6 months

• current smokers of cigarettes/marijuana/e-cigarettes/vaporisers

• anyone unable to comprehend the study protocol or provide informed consent (i.e. dueto English language or cognitive difficulties)

• Participants will not have seen a dietitian in the preceding 3 months.

• score on K10 ≥30 (Kessler Psychological Distress scale)

• score on EDEQ ≥2.8 (Eating Disorder Examination Questionnaire)