The Fast Track to Health (or Fast Track) is a 12 month study looking at the effect of two different dietary patterns on health, psychological well being, eating behaviours, weight loss and risk factors for heart disease and diabetes.

The diets being compared in this study are an Intermittent Energy Restricted plan, and a standard care Reduced Calorie plan. At the moment, we do not know which dietary pattern may be the most effective at reducing weight and improving cardiometabolic risk factors. We aim to test this, and understand which aspects of each dietary pattern are acceptable to young people. It may be that both patterns are effective, finding this out is also important so we can offer more choice and help treat young people with weight concerns in the future.

Intermittent Energy Restriction

This is a very low energy diet for 3 days per week (approximately 25-35% of estimated daily energy needs or 600-700 calories/day) and a standard healthy diet for 4 days per week.

Reduced Calorie Diet

This is a moderately low energy diet with higher fibre foods.

A dietitian will provide each participant with a meal plan and detailed information to support them to follow their plan. The dietitian will ensure each participant’s meal plan is nutritionally adequate for their needs.

Who can participate in the study?

Young people aged 13-17 years with obesity are eligible to participate.

Inclusion Criteria

  • Adolescents aged 13–17 years (inclusive)

  • Obesity (defined as equivalent to adult BMI 30–45 kg/m2, BMI>95th percentile CDC growth charts) with at least one of the following metabolic complications:

  • Pre-diabetes: impaired fasting glucose (5.6-6.9mmol/L) and/or impaired glucose tolerance 2 hours post-load (7.8-11.1mmol/L)

  • Insulin resistance: fasting insulin (pmol/L)/glucose (mmol/L) ratio >20

  • Presence of acanthosis nigricans

  • Hypertension: systolic and/or diastolic blood pressure above the 90th percentile for sex, age and height

  • Low HDL-C <1.03mmol/L

  • High triglycerides ≥1.7mmol/L

  • Abnormal Alanine Transaminase (ALT) or Gamma-Glutamyltransferase (GGT) based on standard PowerChart cut-points (i.e. ALT or GGT >45U/L)

  • Previous diagnosis of polycystic ovary syndrome (PCOS)

Exclusion Criteria

© World Obesity

© World Obesity

  • Secondary obesity

  • Significant intellectual disability as documented by the referring doctor

  • Significant medical or psychiatric illness

  • Currently undergoing treatment for a clinical eating disorder

  • Pregnancy, or planning to become pregnant within the next 18 months

  • Taking medications that have an effect on weight in the short term (excluding metformin)

  • Previous diagnosis of type 2 diabetes

  • Adolescent or parent with poor level of spoken English

  • Current enrollment in a weight loss program

  • BMI in excess of 45 kg/m2

What will the study involve?

All participants will progress through three phases during the study.

Phase 1: Everyone will follow a Very Low Energy Diet to kick-start weight loss for the first 4 weeks. This involves having 3-4 meal replacements and a small meal each day. Meal replacements will be provided free of charge.

Phase 2: Each person will be randomised to receive the intervention. There is not a choice of which pattern to follow.

Phase 3: Everyone will continue to follow the plan they were given in Phase 2, with support from the dietitian. 


Participants are expected to attend 10-13 appointments with a parent/carer at one of the study locations at The Children’s Hospital at Westmead in Sydney, the Be Active Sleep Eat (BASE) Facility at Monash University or Monash Children’s Hospital in Melbourne to meet with the dietitian and other health professionals. Some of the consultations may be via Skype, Facetime or on the phone. Additional support will be provided from a dietitian via text message, email, and phone calls and via social media.

Benefits of participating in the study

The guidance and support the participant will receive from the dietitian and other health professionals may help him/her manage their weight. It is also possible that as a result of following the meal plan and losing weight, the participant’s risk factors for heart disease and diabetes will improve.

How to refer your patients to the study

Check if your patients are eligible to participate in Fast Track here.

To refer your patient to Fast Track, please submit the online referral form below.