Patient Suitability


Intensive level

The Intensive level of the OPTIFAST VLCD Program can be considered in individuals with a BMI > 30, or a BMI > 27 plus risk factors, poor mobility, or a need for weight reduction prior to surgery.

Risk factors include:

  • smoking
  • hypertension
  • dyslipidaemia
  • hyperglycaemia
  • family history of heart disease
  • sleep apnoea
  • over 45 years of age with a BMI of >27

Medical supervision is always advised when following a VLCD program.

Many patients who require weight loss will not present to you asking for assistance. A proactive approach may be required.

A good way to identify patients who are suitable for a very low calorie diet is to classify them by BMI or waist circumference, distribution of body fat, morbidity of complications, age, and readiness to commit.

In addition to the appropriate BMI, suitable patients may include those with:

  1. Waist circumference measurement:
    1. >102cm in men and
    2. >88cm in women
  2. A need for rapid weight loss e.g:
    1. prior to elective surgery,
    2. to allow for increased mobility, or
    3. an improvement of an obesity related medical condition
  3. A history of failure with diet and exercise with or without pharmacotherapy
  4. Motivation and high readiness to undergo the strict supervision and discipline of the OPTIFAST VLCD Program.

If your patient’s BMI is less than 30 and they have no risk factors you can still recommend the OPTIFAST VLCD program however you may consider starting them at the Active 2 or Active 1 level.

Intensive requirements

Active 2 level

The Active 2 level (six weeks) of the OPTIFAST VLCD program is suitable for those with a Body Mass Index (BMI) of 25-30 or for individuals that may find the Intensive level too restrictive.

The Active 2 level restricts calorie intake but not as much as the Intensive level and if combined with regular exercise a weight loss of approximately 1-2kg per week can be achieved.

Unlike the Intensive level the Active 2 level doesn't work by inducing ketosis. It works purely by restricting calorie intake to less than 1000 calories per day.

During the Active 2 level two meals each day will be replaced with an OPTIFAST VLCD product. Two cups of low starch vegetables and to drink 2 litres of low calorie fluids will also need to be consumed. The third meal should be a low calorie meal of around 400 calories. One serve of fruit (approximately 70 calories) and 1 serve of dairy (approximately 100 calories) are also included bringing the total food intake, including the OPTIFAST VLCD products, to approximately 800-1000 calories a day.

Active 2 program


Active 1 level

The Active 1 level (four weeks) of the OPTIFAST VLCD program is when one meal per day is replaced with an OPTIFAST VLCD product.

One OPTIFAST VLCD sachet or bar is consumed in addition to two low calorie meals of approximately 400 calories each. Two cups of low starch vegetables and 2 litres of water should also be consumed as well as, 2 serves of fruit (around 70 calories each) and 1 serve of dairy (around 100 calories).

This phase restricts calorie intake to between 1000 and 1200 calories per day.

The Active 1 level can be used as a meal replacement program for individuals with a BMI of 25-30 kg/m2 who want to lose weight but for whom the Intensive level is not suitable.

Some people may choose to stay on the Active 1 level long term as part of a long term weight management strategy.


Active 1 program


View the patient contraindications

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