Frequently Asked Questions

VLCD stands for "Very Low Calorie Diet".

A VLCD is a low carbohydrate, total diet replacement for the dietary management of obesity. It provides 800 calories or less per day, whilst consisting of sufficient protein, fatty acids, carbohydrates, vitamins and minerals for safe and fast weight loss.

Very low calorie diets (also known as VLEDs or Very Low Energy Diets) have been shown to be very effective in the management of obesity, with weekly weight losses averaging approximately 1-2.5kg per week, providing greater initial weight loss than other forms of calorie restriction.

Reducing energy (calorie) intake to less than 800 calories as well as reducing carbohydrate intake leads to a whole body shift towards fat stores being utilised as the major source of energy through a process called ketosis. This results in consistent and successful weight loss.

In comparison, a formulated meal replacement means a single food or pre-packaged selection of foods that is sold as a replacement for one or two of the daily meals but not as a total diet replacement. A formulated meal replacement does not work by inducing ketosis to assist with weight loss. It works purely by restricting overall calorie intake.

The OPTIFAST VLCD Program is a very low calorie diet program, which consists of 4 levels. The Intensive Level is the very low calorie diet part of the program, which is a total diet replacement providing up to 800 calories. Following this is the Active 2 Level, Active 1 Level, and Maintenance Level, where food is gradually re-introduced and OPTIFAST VLCD products are reduced and then eliminated.

It is recommended to start the OPTIFAST VLCD Program at the Intensive Level for a period of up to 12 weeks, then gradually move through the next three levels of the program.

However, the OPTIFAST VLCD Program is designed to be flexible and to fit within individual needs. If you find that the Intensive Level is not suitable, you can consider starting the program on either the Active 2 or Active 1 Level, after consultation with your healthcare professional.  On the Active 2 or Active 1 Levels of the program, your rate of weight loss will be slower than the Intensive Level. Please consult your healthcare professional to determine your suitability for the OPTIFAST VLCD Program.

There are 3 Levels for active weight loss in the OPTIFAST VLCD Program which are the Intensive Level, Active 2 and Active 1 Levels. Once you have achieved your goal you can move into Level 4 which is Maintenance.

Although most individuals will start at the Intensive Level and work their way through to the Maintenance Level, you can start at the Level that best suits your lifestyle needs and weight loss goals.

The Intensive Level of the OPTIFAST VLCD Program is the Very Low Calorie Diet  part of the program. It is a total diet replacement providing less than 800 calories per day. This level is designed to achieve a large initial weight loss whilst helping to preserve lean body mass. You can stay on this level for anywhere up to 12 weeks, however, this period is variable and depends on your weight loss goals.  If there is still a significant amount of weight to be lost at the end of the initial 12 weeks, we recommend you follow the Active 2 Level for a minimum of two weeks before repeating the Intensive Level again. In some instances if you are doing well on the Intensive Level and still have more weight to lose at the end of the initial 12 week period, your healthcare professional may advise for you to stay on the Intensive Level for longer. It is very important to note that this should only be done under the instruction and supervision of your healthcare professional.

The OPTIFAST VLCD Program Levels are intended to assist you to lose weight quickly. The goal of the remainder of the levels following completion of the Intensive Level is to assist you to continue to lose weight but also to develop healthy eating habits for the long term. By slowly re-introducing food back into your diet you are setting healthy new patterns that are sustainable for the rest of your life.

OPTIFAST VLCD Program should always be used under the supervision of a healthcare professional. They may sometimes advise a different regimen based on your health needs.

CODEX Standard 203-1995 (International Food Standards) defines very low energy or calorie diets as containing 450-800kcal per day. This total calorie intake per day represents the products as well as additional foods consumed.