Medical Monitoring

Medical Monitoring

Supervision by a Healthcare Professional

OPTIFAST VLCD must be taken under the supervision of a healthcare professional such as a dietitian, doctor, pharmacist, diabetes educator or other trained healthcare professionals. 

To assist in your knowledge and implementation of the Program, you can undertake our comprehensive training and become an Accredited OPTIFAST VLCD Healthcare Professional (more to come soon).

 As a healthcare professional you can tailor the Program to suit your patients' specific likes and dislikes, medical conditions, nutritional needs, physical activity levels and lifestyle. 

If your patient has a co-existing medical condition, then you may need to monitor them more closely or even adjust their medication dosage.

Research has shown that having the support and guidance of a healthcare professional will make the Program more successful.

It is recommended that once a patient has commenced on the Intensive level of the OPTIFAST VLCD Program they should be followed up fortnightly for check-ups, weight and waist circumference monitoring, advice and encouragement.

Patients can be classified as low medical risk, or high medical risk when following a VLED. For all patients, regular monitoring of weight, BMI, waist circumference and blood pressure is recommended during the Intensive Level of the OPTIFAST VLCD Program.

Regular blood monitoring is important during the Intensive level of the OPTIFAST VLCD Program for 'high risk' patients because of the risk of electrolyte imbalance.  Please see below for the recommended blood tests and medical monitoring during the Intensive Phase of the OPTIFAST VLCD Program.

Medical MonitoringMedical Monitoring

Side Effects

The Intensive Level of the OPTIFAST VLCD Program is accepted as being safe with only minor, transient side effects being observed.

These side effects are generally the result of the fast weight loss and ketosis and may include;

•    Sensitivity to cold
•    Halitosis
•    Headache
•    Hair loss
•    Irritability
•    Postural hypotension
•    Fatigue
•    Muscle cramps
•    Menstrual disturbances
•    Constipation and, or diarrhoea

These side effects are generally insufficient in magnitude or duration to warrant cessation of the program.

As with any major dietary adjustment, the first few days on the Intensive Level of the OPTIFAST VLCD Program can be difficult and are commonly known as the '3-day challenge'.

As the body transitions into ketosis, patients may experience some transient side effects in the first three days, such as:

Lack of concentration

Typically, only mild ketosis occurs during the Intensive level of the OPTIFAST VLCD Program, and most symptoms pass by days 4-6.  By this time, users will experience an increase in energy and reduction in appetite, which, through the Intensive level, is likely to result in consistent and successful weight loss.  

Tips for managing side effects

Careful management of the side-effects during the Intensive Level of the OPTIFAST VLCD Program can significantly increase the success of the program as well as the patient's compliance.

It is important to note that some initial side-effects, especially during the first three days of the Program, are typical and can be easily managed.  Please see the tips below on how to manage the more common side-effects

Headaches, fatigue, lack of concentration, nausea
Side effects such as headaches, fatigue, lack of concentration and nausea can occur in the first couple of days as the body transitions into ketosis.  Encourage your patients to stick to the program as prescribed and to avoid eating any extra food during this initial three days; otherwise, they will just prolong the uncomfortable feeling.  If your patient has quite an intensive job, recommend that they start the program on a weekend where they will have more time to rest, as this may assist with them managing their symptoms.  If your patients continue to experience some of these symptoms, consider adding in 1-2 cups of stock, broth or bouillon to the daily meal plan. When following a carbohydrate-restricted diet for more than two weeks, our body switches from retaining salt to rapidly excreting salt, along with stored fluid.  Some of these symptoms can be due to an electrolyte imbalance and can be easily and quickly rectified with the addition of some extra sodium11.

It is normal to feel hungry for the first few days of the program as the body transitions into ketosis.  If possible, encourage your patient not to eat any extra food to compensate for the fatigue or hunger. However, if they are struggling then recommending to add in a small serve of lean protein each day may help manage their hunger feelings while they adjust to ketosis. They must avoid foods that contain carbohydrates, as this will stop ketosis from occurring. If hunger is a problem while on the OPTIFAST VLCD Program, make sure fluid intake is adequate as we sometimes mistake hunger for thirst.  Also, you can recommend they distract themselves with another activity such as going for a walk or taking a bath.  If all else fails use the foods listed in the Additional Allowances table, to increase intake or have some sugar free lollies which may also help with bad breath.

A complete meal replacement program is usually a dramatic change of intake for most people, and this can cause changes in bowel habits. In addition, if the recommended fluid and low starch vegetables are not consumed, a lack of fibre (dietary bulk) and fluid can result in constipation.  It's important to know the difference between going less frequently and true constipation.  It is normal to go less frequently when consuming less food, whereas true constipation is when the consistency is also affected. If your patient is experiencing constipation, recommend they consume more than the 2 cups of low starch vegetables per day, drink 2-3 litres of fluid, and ensure they are exercising daily to help keep the bowels healthy and regular.  If they still find they are constipated suggest a fibre supplement.  Additionally adding 1-2 cups of stock, broth or bouillon to the daily meal plan also helps rectify symptoms of constipation11

Diarrhoea can be a temporary side effect of taking OPTIFAST VLCD products and should pass with time (refer to leaflet product packaging under 'Adverse Reactions').  If diarrhoea continues for more than a week, you may need to investigate for further causes.

Bloating /flatulence
There could be several explanations to explain bloating or an increase in flatulence. Bloating/increase flatulence may be caused by the change in diet.  If there is more fibre in the new regimen due to increased intake of vegetables, this may result in the bloating.

Some people find that they feel bloated because they are drinking a lot more fluid than usual.  The bloating /increased flatulence is usually transient and resolves quickly, so it is recommended to keep progressing with the program.

Alternatively, if your patient is lactose or fructose intolerant, the OPTIFAST VLCD products may cause bloating as they contain one or both of lactose and fructose.  If the symptoms don't improve within a week, it may be worth doing some further investigation.

Estimated fluid requirements are 35-45mL/kg Adjusted IBW/day. 
For most patients greater than 80kg, this will equate to approximately 2.5-3.0 L/day.  As three sachets of OPTIFAST VLCD provides about 600mL per day, most patients on the OPTIFAST VLCD Program Intensive Level will require an additional 2 L per day of fluid, preferably water.

Nutritional Deficiencies / Supplementation
The OPTIFAST VLCD Intensive level (3 OPTIFAST VLCD products plus 2 cups of vegetables) is designed to meet the recommended dietary intake for most people.  Therefore, additional supplementation is not necessary unless there has been a pre-existing nutritional deficiency diagnosed when starting the OPTIFAST VLCD Program.  If additional supplementation is desired, care would need to be taken to ensure that recommended safe levels of vitamins, minerals and trace elements are not exceeded.

Fish Oils
Fish oil supplementation is considered relatively safe, and there is substantial research regarding the benefits of Omega-3, particularly in the area of cardiovascular health.  The Australian dietary target to reduce chronic disease is 430mg for females and 610mg for males16. The National Heart Foundation has set the recommendation of 500mg per day for all adults to help reduce the risk of heart disease17.  The OPTIFAST VLCD Shakes, Soups and Desserts contain on average 70mg of omega-3 (combined EPA/DHA) per serve (the Bars currently do not contain fish oil).  If additional fish oil supplementation is desired for health benefits, then this will be safe to include as part of the OPTIFAST VLCD Program.

Fast weight loss may induce the formation of gallstones. Historically, fat intake was very low with a VLED; therefore, the addition of fat (i.e. 1 tsp vegetable oil per day) was recommended to stimulate the emptying of the gallbladder. Most of the OPTIFAST VLCD products contain levels of fat which include omega-3 fatty acids; therefore, the addition of the teaspoon of vegetable oil is less relevant.  However, for compliance and adding flavour to vegetables, it can still be added.  If consuming the OPTIFAST VLCD Bas only, the addition of the teaspoon of vegetable oil will be necessary to provide omega-3 fatty acids.

Bad breath or halitosis can occur while using the OPTIFAST VLCD Program. This is caused by ketosis and generally due to an increase in acetone levels.  This is characteristic of ketogenic-type diets and indicates compliance with the program. The halitosis will only last while they are following the Intensive level of the OPTIFAST VLCD Program.  Recommending chewing on a low-calorie mint or sugar-free chewing gum can help.  Eating fresh parsley can also be very effective.

Find out about measuring ketones here.

Measuring Ketones

Measuring ketone levels can be used as a guide for assessing compliance. It is not compulsory to measure ketone levels, but some patients may find it useful.  Ketones can be measured via urine, breath or blood. Monitoring symptoms and side-effects can also be a good indication of whether an individual is in ketosis.

Urine ketone strips
Urine ketones can be measured using ketone reagent strips.  The OPTIFAST VLCD Intensive Level only causes a mild ketosis; therefore, urine ketone levels will only show approximately 0.5-1.5mmol/L.  Urinary ketone levels can be higher early on in the program so can be a good initial indicator of compliance; however, levels excreted in the urine decrease as the body starts to use more of them as energy.  In addition, ketone reagent strips only measure acetoacetate but tell you nothing about the level of ketones in your bloodstream (BHB) which is most probably higher.

Breath testing
A non-invasive and cheap alternative is to measure breath acetone concentration. Acetone is one of the ketone bodies that results from a breakdown of acetoacetate.  Ketone breathalysers are available and offer an easy and inexpensive way to test your breath ketones (acetone). There is an initial outlay in cost to purchase the breathalyser however you won't need to purchase reagent strips.  Keep in mind that breath ketones do not always precisely correlate with blood ketones and are affected by several factors such as alcohol consumption and water.

Blood testing
Blood ketone meters are the most accurate way to measure ketone bodies. They can precisely determine the level of ketones in your blood but can be more expensive than breath and urine testing.  Blood ketone meters can be purchased from pharmacies or online.

Monitoring symptoms is another way of assessing ketosis.  When in ketosis, the smell of acetone is present in the breath, sweat or urine. Some people refer to this as ketogenic "fruity" smelling breath.

Help your patients chose which OPTIFAST VLCD products are suitable for them by reading the managing allergies and intolerances page. 

Managing allergies and intolerances

Your patients can still follow the OPTIFAST VLCD Program if they have allergies or intolerances. It is just a matter of working out which OPTIFAST VLCD products will suit them best. Different products in the OPTIFAST VLCD range have different allergens present. This table lists the allergens present in each of the OPTIFAST VLCD products, to allow you to choose the most appropriate choice.

Allergens present in the OPTIFAST VLCD range

Allergen Product Information


Lactose Intolerance
All the OPTIFAST VLCD products contain some quantity of lactose. The amount of lactose may be tolerated by some people; however, it can be individual, and it may be a matter of trial and error to see what products your patient can manage. OPTIFAST VLCD Protein Plus Shakes and OPTIFAST VLCD Bars are low in lactose and may be more suitable for individuals with lactose intolerance. Alternatively, you can recommend a lactase enzyme tablet with your OPTIFAST VLCD product. Lactase enzyme tablets are available from your local pharmacy.

Lactose content of the OPTIFAST VLCD product range

Lactose Content of Products

Fructose Malabsorption

The OPTIFAST VLCD Shakes, Soups and Desserts do not contain any fructose, and therefore may be appropriate for those with fructose malabsorption. The Bars contain a small amount of fructose and therefore may not be appropriate; however, it may be a matter of trial and error to work out which products are better tolerated.

Fructose content of OPTIFAST VLCD product range

Fructose Content of Products


FODMAPs refer to Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols. Research shows that reducing the intake of these sugars in the diet can improve symptoms associated with Irritable Bowel Syndrome (IBS). This group of sugars include fructose, lactose, fructans, galactans and polyols.

In individuals with IBS or other gut disorders, these sugars are poorly absorbed in the small intestine. They therefore travel to the large intestine where they are fermented by bacteria that are naturally present. This process can cause symptoms such as gas (wind), pain, bloating, diarrhoea or constipation.
The table below highlights the OPTIFAST VLCD products that may contribute to the FODMAP load.

FODMAPs content of the OPTIFAST VLCD range

Medical Monitoring

Exercise is an important component of any weight loss program. Click here for more information.


Exercise recommendations

Physical activity is essential for many reasons.  Not only does it contribute to part of the energy balance equation and play a role in weight management but is also an important part of an individual's emotional well-being and provides many health benefits such as reducing blood pressure and blood glucose levels.

For this reason, increasing physical activity in patients undergoing the OPTIFAST VLCD Program is highly recommended. The general goal of physical activity in weight management is to increase an individual's energy expenditure as well as and resting energy expenditure (REE).  Research indicates however that during a period of weight loss induced by energy restriction, absolute REE tends to decrease, and neither resistance or aerobic exercise has been shown to prevent the decreases in REE that is typically observed 18, 19.   However, aerobic and resistance training during weight loss has been shown to prevent the normal decline in fat-free mass and increase muscular strength and aerobic fitness compared with diet-induced weight loss alone, so in this respect, it may offer some long-term benefits following weight loss. 

Exercise doesn't appear to significantly accelerate the amount of weight loss that is achieved by the VLED alone, 19, 20 however it does seem to offer benefits in terms of weight loss maintenance and preventing weight regain 21. The minimal recommended level of physical activity that will improve health is 150 minutes/week or 30 minutes of moderate exercise 5 days per week22.  Although this is the minimal amount that should be achieved, research suggests that this may not be enough to prevent weight regain following a period of weight loss21.  Data collected from the National Weight Control Registry of individuals that have maintained a weight loss of approximately 30kg for six years reported participating in 2500-3000 kcal/week of leisure-time physical activity23.  This would be the equivalent to 60-100 minutes of brisk walking five days per week. This data does not suggest that the minimum recommended guidelines are ineffective but simply indicates that this is a minimum to aim for with your patients, and then once this is achieved aim to increase further.

Exercise should include both planned physical activity (i.e. walking for a set time each day, training at a gym or with a personal trainer, team or individual sports) as well as increases in daily activity (e.g. reducing sitting time and sedentary activities, walking to and from transport, using stairs rather than lifts, parking car further away from the desired destination, getting up from computer or desk regularly, lifestyle approaches such as gardening, house cleaning etc.).  It has been suggested that lifestyle approaches to increasing physical activity such as gardening and house cleaning may be effective in managing body weight so these shouldn't be dismissed and may be easier to achieve for time-poor individuals24.

For most patients that haven't exercised for an extended period of time, starting small and building can be a good place to start.  Repeated bouts of 10 minutes of activity can equal that of one 30 or 40-minute block of exercise.  This method may facilitate the initial adoption of activity in previously sedentary individuals25,26.

For patients participating in exercise at a high level for periods longer than 60 minutes, a higher protein intake may be required.  This can be provided by adding a small amount of meat, fish or eggs (60-100g) to the salad or vegetable plate, the addition of a pure protein powder such as BENEPROTEIN or having an extra serve of OPTIFAST VLCD per day.  It is also important when exercising to ensure fluid intake is adequate.

Australian physical activity recommendations for adults27

1. Doing any physical activity is better than doing none.  If you currently do not do any physical activity, start by doing some and gradually build up the recommended amount.


2. Be active on most, preferably all, days every week.


3. Accumulate 150 to 300 minutes (2½ to 5 hours) of moderate intensity physical activity or 75 to 150 minutes (1¼ to 2½ hours of vigorous intensity physical activity, or an equivalent combination of both moderate and vigorous activities, each week.


4. Do muscle strengthening activities on at least 2 days each week.




Practical information to support weight management through physical activity3,27 

1. Provide ideas for increasing the amount of incidental activity, for example: 


a. Choose stairs rather than lifts 


b. Park further away from destination and walk

c. Use public transport rather than driving

d. Walk to do errands

e. Use a community bicycle

f. Use a pedometer to measure the number of steps achieved each day – aim to get 10,000 steps

g. Limit screen time

h. Look at lifestyle approaches such as gardening and housecleaning as a way of increasing physical activity levels.


2. Provide ideas for low impact/low risk exercise options:

a. Aqua aerobics or hydrotherapy

b. Walking or low impact gym machines

c. Yoga or Pilates


3. Suggest to exercise with others such as family, friends, partners or children to help maintain motivation.


4. Explain the relative benefits of different types of exercise intensity and how this need to increase as fitness levels increase.


5. Suggest how to get involved in physical activity events or groups.   


We also provide lots of tips on how to manage non-compliance in our next section. Click here.


Managing non-compliance

Despite the best intentions, there may be circumstances in which a patient is finding it difficult to comply with the OPTIFAST VLCD Program. Listed below are some possible difficulties your patient may raise with you and answers to help guide you.

I am finding it difficult to have OPTIFAST VLCD at work
If making the Shakes at work is just not practical, try taking the OPTIFAST VLCD Bars instead. This way, you don't need to prepare anything. Remember to always include a salad along with the Bar as this will help fill you up with fibre, vitamins and minerals as well as help you feel as though you are consuming a regular work lunch. Another idea is to use a wide brim sports bottle to mix up your OPTIFAST VLCD Shakes. Simply add the powder to the bottle, add 200mL or more of chilled water, pop on the lid and shake.

I am used to having a snack between meals.
OPTIFAST VLCD products do not need to be restricted to mealtimes only. You can try splitting an OPTIFAST VLCD Bar in two, and have half at morning tea, the other half at afternoon tea and have a salad or vegetables at lunch. You could also try Miso soup or diet jelly between meals, and don't forget that low-starch vegetables can be used as a snack at any time. If you are on the Active 2, Active 1 or Maintenance Level of the OPTIFAST VLCD Program, 1-2 pieces of fruit or low-fat yogurt (~150g) can be consumed as a snack between meals. Make sure you are drinking plenty of water and getting adequate sleep each night to make sure your hunger signals are not signals of thirst or tiredness.

I am just too hungry; it is too restrictive.
If followed correctly, most people find after the first week that appetite is controlled during the Intensive Level of the OPTIFAST VLCD Program. If additional carbohydrates are avoided, your body should enter a state of ketosis, and this chemical reaction, in turn, reduces your appetite. If you are struggling to stick to the program, you can include some lean meat or fish in the first week before the onset of ketosis to help manage hunger levels. Many people are surprised that the Intensive level may be easier to adhere to than the later levels in the diet when ketosis is mild or not present. Remember to stick to the OPTIFAST VLCD Program and only have the foods recommended on the plan along with your OPTIFAST VLCD products. To make sure the signals of hunger are not getting confused with other body signs, drink the recommended 2 litres of water daily, have the recommended serving of low starch vegetables and get sufficient sleep each night. Ask yourself if it is true hunger or whether you are eating because you are bored or stressed.

I seem to have hit a plateau and my weight is not moving any more.
It is not unusual to experience a plateau during an extended weight loss program. Remember, as you lose weight, the energy cost of moving your lighter body during daily tasks and exercise is much less, which makes it harder to burn up the calories. Review your plan and make sure that it is still on track. Other things you may need to consider are increasing the intensity of your exercise in order to burn more calories or alternatively look at ways to increase your daily activity levels; that is the amount of movement you are doing during the rest of your day. There are many Apps, fitness trackers and tools to measure your daily activity. Try aiming for 8,000-12,000 steps per day, increasing up to this amount gradually from your current level of activity.  

I have too many social outings involving eating out and I don't want to miss out on these.
Suggested answer for Level: Intensive

That's ok; you can still enjoy social occasions while on the OPTIFAST VLCD Program. Your life doesn't have to stop, nor should it have too. Try to focus on the other aspects of socialising such as the people you are with and the location rather than focusing solely on the food and drink. 

Try having your OPTIFAST VLCD product before going out and then choose a low starch salad or vegetables. Try a Miso soup, stir-fry vegetables, or a garden salad with the dressing on the side (no creamy sauces). If possible, skip the protein and carbohydrates on offer. If you must eat something other than just the vegetables or salad, miss the OPTIFAST VLCD product for that meal and opt for a small portion of protein such as 100g meat or chicken, some fish or eggs. Avoid the carbohydrates as this will affect ketosis. Remember, it is important not to drink alcohol while on the Intensive Level of the program. Try some mineral water with a spritz of lemon or lime instead.

Suggested answer for Levels: Active 2 and Active 1 

That's ok; you don't need to miss out on your social outings. Choose grilled meat, chicken or fish with a side salad or cooked low starch vegetables. Always ask for the sauce/ dressing on the side so you can control the amount that is put on the meal (if any). Always pick your own meal, avoid banquets and sharing meals. If possible, get a copy of the menu prior to going out so you can take your time to review the menu options. Avoid alcohol - have a sparkling mineral water with a wedge of lemon or lime in it, or a diet soft drink served in a champagne or wine glass.

It is winter, and the thought of having shakes and salads is not comforting in the cold weather.
Try making your Shakes with warm water (not boiling) or try the OPTIFAST VLCD Soups. During the winter months we often divert from salads to cooked vegetables, so do the same on the OPTIFAST VLCD Program. There are plenty of low starch vegetables you can cook up with a tomato-based sauce. Why not make a hearty winter soup from the allowed vegetables or see our list of healthy recipes on the website.

I am getting constipated.
A total diet replacement program is usually a dramatic change of intake for most people, and this can cause changes in bowel habits. In addition, if the recommended fluid and low starch vegetables are not consumed, a lack of fibre (dietary bulk) and fluid can cause a dramatic change. It's important to know the difference between going less frequently and true constipation. It is normal to go less often when you are consuming less food and only considered true constipation if the consistency is also affected. Try to consume more than the recommended 2 cups of low starch vegetables per day, drink 2-3 litres of fluid, as well as exercise daily to help keep your bowels healthy and regular. If you still find that you are constipated try a fibre supplement.

Everyone around me is concerned that the diet is too strict.
The OPTIFAST VLCD Program has three levels for active weight loss. Where appropriate, we encourage people to start on the Intensive Level as this is where the most significant weight loss occurs. This part of the Program is the 'Very Low-Calorie Diet' component, (where you replace all three meals with OPTIFAST VLCD products) and been shown to be safe and effective for fast weight loss. If the Intensive Level is not suiting your lifestyle, you can move to a more gradual weight loss program in Active 2 or 1 Levels. Importantly, the program is flexible. You can move between levels as your patients' goals or lifestyle needs to change over time.

It is too boring.
When you stick to the same thing for an extended period, anything can become boring. To make things a little more interesting, vary the OPTIFAST VLCD products as much as possible rather than sticking to the same products each day. Also, play around with the way you prepare your salads and vegetables. Don't just have them plain - try adding fresh or dried herbs and spices and buy vegetables you wouldn't normally eat to create variety. Adding lots of different colours on the plate is important to help make the meal look appealing, while also getting a range of vitamins and minerals which are vital for optimal health.

People keep saying I have lost enough weight and should stop.
It's hard enough for individuals to adjust to their new eating habits and body image, but it is common and sometimes even harder for others around you to adjust. Dramatically changing to a healthier lifestyle can start people questioning themselves and whether they need to change too. Your healthcare professional will advise you on your weight loss progress and provide tips to help deal with the adjustment you and the people around you are making.

I don't fit into any of my clothes anymore; I will have to stop.
Although visiting the clothing store seems like a daunting experience, it's not a reason to stop your desire to be a healthier weight. Change is a good thing when it means progression and moving in the right direction. Ask friends and family to borrow clothes while you transition into your new body size, as you won't want to buy too many clothes if you plan to lose many more dress or pant sizes. You may consider shopping at opportunity stores or hiring a business suit during the Intensive Level of weight loss or until you have reached your goal weight.

I don't seem to have enough energy at the gym.
Weight loss is all about eating less energy than what you are burning. High-intensity exercise uses predominantly carbohydrates. On the Intensive level of the OPTIFAST VLCD Program, you are consuming minimal carbohydrates; therefore, you may find lower intensity exercise and weights a little easier to handle. You may also want to change the time you exercise – so tiredness from the day doesn't play a factor. Choosing exercise that you enjoy will always improve motivation levels, as can exercising with a friend. Even if your exercise intensity and duration slightly reduces (but not to nothing) while you are on the OPTIFAST VLCD Program, some exercise is still better than none as it dramatically improves your metabolism and helps you preserve metabolic muscle tissue while burning the fat in your body. Remember, drinking sufficient fluids and getting adequate sleep will also help improve your energy and motivation to exercise.

I keep getting headaches.
The first few days of the OPTIFAST VLCD Program Intensive Level is known as 'The 3 Day Challenge' because, as the body transitions into ketosis, you may experience some side effects such as:

  • Fatigue
  • Hunger
  • Nausea
  • Headaches
  • Lack of concentration

This doesn't sound pleasant, but most symptoms pass by days 4-6, followed by an increase in energy and reduction in appetite, of which, through this dietary phase will result in consistent and successful weight loss. It is essential that you know these are typical symptoms, and you should stick to the weight loss plan as prescribed, or you will simply prolong this slightly uncomfortable few days of your OPTIFAST VLCD Program.

I'm not losing any weight.
This is very unlikely on the Intensive Level of the OPTIFAST VLCD Program. If you are not losing weight and you are sticking to the plan as prescribed, then reasons for your inadequate weight loss may need to be explored. If you haven't been exercising, consider starting walking or going to the gym. The combined effects of exercise plus a VLED have been shown to increase the retention of lean muscle mass and reduce fat mass. If just starting with exercise, it is important to establish a baseline which can be improved upon each week. If you are concerned with your weight loss, speak to your healthcare professional for further investigation. 

To learn more about Long-term weight management with the OPTIFAST VLCD Program, click here.


11.    Volek. J.S. and S. Phinney, The Art & Science of Low Carbohydrate Living. 2011.
17.    Foundation, N.H., Fish, Fish Oils, n-3 polyunsaturated fatty acids and cardiovascular health. 2008.
18.    Kraemer, W.J., et al., Influence of exercise training on physiological and performance changes with weight loss in men. Med Sci Sports Exerc, 1999. 31(9): p. 1320-9.
19.    Donnelly, J.E., et al., Effects of a very-low-calorie diet and physical-training regimens on body composition and resting metabolic rate in obese females. Am J Clin Nutr, 1991. 54(1): p. 56-61.
20.    Geliebter, A., et al., Effects of strength or aerobic training on body composition, resting metabolic rate, and peak oxygen consumption in obese dieting subjects. Am J Clin Nutr, 1997. 66(3): p. 557-63.
21.    Jakicic, J., The Role of Physical Activity in Prevention and Treatment of Body Weight Gain in Adults. American Society for Nutritional Sciences, 2002. 132: p. 3826S-3829S.
22.    Haskell, W.L., et al., Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association. Circulation, 2007. 116(9): p. 1081-93.
23.    Klem, M.L., et al., A descriptive study of individuals successful at long-term maintenance of substantial weight loss. Am J Clin Nutr, 1997. 66(2): p. 239-46.
24.    Andersen, R.E., et al., Effects of lifestyle activity vs structured aerobic exercise in obese women: a randomised trial. Jama, 1999. 281(4): p. 335-40.
25.    Jakicic, J.M., et al., Effects of intermittent exercise and use of home exercise equipment on adherence, weight loss, and fitness in overweight women: a randomised trial. Jama, 1999. 282(16): p. 1554-60.
26.    Jakicic, J.M., et al., Prescribing exercise in multiple short bouts versus one continuous bout: effects on adherence, cardiorespiratory fitness, and weight loss in overweight women. Int J Obes Relat Metab Disord, 1995. 19(12): p. 893-901.
27.     Department of Health and Aging., Physical Activity Gruidelines for Adults. 18-64. 2014.