Very Low Calorie Diets (VLCD’s)

 By Mizpah Matus B.Hlth.Sc(Hons)

very-low-calorie-dietsA Very Low Calorie Diet (VLCD) is a diet where normal meals are replaced with drinks, soups, or bars.

The typical daily calorie intake is on or under the 800 Calorie mark – however the aim is to be as nutritionally balanced as possible.

These diets are popular because initially people can lose a lot of weight quickly.

However, if a VLCD isn’t done correctly it can have negative consequences on a dieter’s health.

Prescription Only

A VLCD is normally only used privately and in the medical profession to bring about rapid weight loss in the dangerously overweight person.


These diets should be undertaken only under medical supervision. They are typically a high fat, high protein diet that will bring about Ketosis.

This is when the body breaks down fat for energy instead of using glucose.

Used for Short Periods Only

The diet is only undertaken for a short period of time (a few weeks). In some situations, the meal replacements may only be used for two meals a day – therefore bringing about slower but more manageable weight loss.

Safe VLCD Diets

MedifastThis has been used by (apparently) over 1 million people, and is endorsed by John Hopkins University. It’s a meal replacement plan around the 800-1000 calories mark (which puts it outside the strict definition of a VLCD). It will put the body into a mild state of ketosis.
OptifastAvailable at hundreds of clinics in the US and Canada. However many find it difficult to complete the program.
The Cambridge DietUsed in the UK, this diet has an even lower daily calorie level (400-600) and is a high protein, low fat, low carb diet.
Bernstein DietFor some patients an 800 calorie meal plan will be perscribed.
Alternate Day DietAlternates one VLCD day of 500 calories with a day of just 20% less calories.
Newcastle DietMedically supervised VCLD that reverses type 2 diabetes.

Dangerous Very Low Calorie Diets

HCG DietThis 500 Calorie diet can be dangerous if not supervised by an approved clinic.
Sacred Heart DietNutritionally deficient and very low in calories.
Cabbage Soup DietThis soup based diet lacks nutrition and is very low in calories.
3 Day DietThis VLCD can be dangerous if done more than 3 days.
Grapefruit DietTouted for grapefruit’s fat burning qualities but the very low calories are most likely responsible for any weight loss.
Mayo Clinic DietThis unofficial diet is based around the grapefruit and very low in calories.


Generally exercise isn’t recommended while a person is on a VLCD as the calories consumed aren’t sufficient to support it.

However, some plans recommend light exercise such as walking or swimming for those with an excessive amount of weight to lose.


Initially people following very low calorie diets can lose a lot of weight, which keeps these diets popular.

However, they can be dangerous long-term because they often lack the nutrition your body needs and can actually crash a person’s metabolism.

If a dieter wants to use a VLCD, he or she should only do so under medical supervision and if extreme weight loss is needed.

 By Mizpah Matus B.Hlth.Sc(Hons)
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  • KBirdmom

    People! PLEASE read up on this before jumping in. Recommended: “The End of Overeating,” Gary Taubes’ “Why We Get Fat and What To Do About It” (A condensed version of “Good Calories, Bad Calories,” Dee McCaffrey “The Science of Skinny.” Bottom line – a diet of ALL fat and protein will help you lose weight, you won’t feel deprived, and you will keep the weight off. Carbohydrates – especially refined and processed – will kill you. If you are an adult-onset diabetic, this is especially true and critical for your future health.

    Atkin’s is the way to go, long-term. I’ve lost 60 lbs. Dee McCaffrey (processed free, aka “clean”) helped me get started, hcg helped boost the loss (medically approved ONLY, don’t buy the over-the-counter variety, which does NOT contain human hcg, but a processed chemically close compound), and I’m keeping it off with proteins/fats only.

    Voice of experience here – and 100% diabetes genes (both mother and father), and I am off all of my meds with a HgA1C of under 6.0.

    Avoid ALL processed foods. Avoid ALL carbohydrates (you don’t really need them – read the literature). You will live longer AND be healthier. Guaranteed.

    Good luck! KB

    • Vanessa

      Omg I totally agree with this! You are right-no carbs are the way to go and high protein!!!

      Thanks for sharing!

    • A. nonymous

      The Crapkins Diet?? Not the way to go. By the time you lose the
      excess fat and flab, you’ll need heart bypass surgery.
      You’re being deceived.

  • Breanna

    Well! I am about 100 pounds overweight. A month ago, I began a diet. I’m young, I’m hoping this will work. As long as your body gets nutrients, the caloric intake does not matter. My regimen consists of eating 600 calories a day, packed of protein and minerals (filling in with multi vitamins!), and jogging two or three miles a day, resistance bands and such. In the end, I MIGHT have taken in a total of 100 calories ( in – out = total ). As I burn 2,000 calories just walking around and cleaning my home at my current weight, the weight should come off. Wish me luck!

    • Drock

      Have you lost weight yet?

      • katy

        LOL that super wrong but i actually wanted to ask DID it Work?

  • Erika

    A few years ago I would have scoffed at VLCD because I was eating super clean and worked out 6 times a week. Now I have a 5 month old, an injured back and a foot that I dropped a cinderblock on that will not heal and I’m only 31! By chance I read an article about how Matt Damon had to lose weight for a role. He ate 1 can of chicken breast and an apple. Now I’m not going that far….I’m planning to eat 2 cans of chicken, 2 pieces of fruit and 2 veggie servings. But along with that I will be taking hcg, multivitamin, calcium, flax seed oil, cinnamon, CLA, and raspberry ketones so I am not depriving my body of nutrients. I plan to do this for a few weeks, then eat fairly clean for a week and do it again. I am 100lbs overweight, yet no doctor in this Podunk town will even draw labs to check hormones and thyroid levels. So we will see what goes on! I’ll try to keep u updated :)

    • Rayca

      I guarantee you that if you do the VLCD every OTHER day, you will drop the weight faster than every day, you won’t lower metabolism (too much) and you may/may not experience some ketosis. Everyone is different. But it’s far better than every day, which is insane. Your weight will drop faster, keeping the body off-balance as to what’s coming next. It’s not zig-zag, it’s not hi-protein, low carb, none of that. Just keep cals. to 500 or below every other day, eat normally on the other days. I guarantee it.

      • ted

        That’s not a VLCD but an Alternate Day Diet or Intermittent Fasting.

  • UMA

    hello even i m starting 700 calorie diet..but i m confused how much protein to consume as i m 5″2 and weigh 143 lbs…could anyone pls suggest me..

  • Kim

    I read the Newcastle study, and “joined” the experiment with a class of one last October 2011. I lost 20kg in 10 weeks and reversed my diabetes. I simply ate normal food but only 600 I am now back on a normal diet without drugs and can be deemed in “long term remission”. If I am still off drugs after 5 years it can be called a cure. I was inspired by the Newcastle study and I wish their message could be more widely spread. “Recently diagnosed Type 2 diabetics should be told that the condition is reversible”.

    • Has Akhtar

      Dear Kim

      I am trying my best to control my type 2 diabetes by reducing starch from my diet. This has enabled me to loose couple of stones in six months and reduce my glucose level averaging now at around 6.5

      I will be grateful if you could please share your experience with me.



    • Yasir

      Dear Kim,

      I was diagnosed with T 2 two months ago. Would you be able to share what you did for the diet with me please.

      Thanks mate!

      • Kathryn

        The symptoms of Type II may indeed be reversible, but will reverse right back if you go back to weight gaining, sedentary lifestyle.

  • teenda

    From my point of view 600 calories per day is a new hope for those who have diabetes .It is ur choice either u want to take medicine for ur whole life and live a tastless life .I don’t want a tastless life so I prefer diet what’s ur opinion friend?

  • Mary

    If I hadn’t suffered from insulin resistance my whole life, I would almost wish that some of you “just eat less” people could deal with it too! But I would never wish this frustration on anyone! For some people, eating less and exercising more does work. For others, it doesn’t. It’s a medical fact. By belitting those of us who need a little extra “help” from our doctors to become healthier, you are only contributing to the problems we already have. Until you have a medical degree and are recognized by the American Board of Bariatric Medicine, kindly keep your uniformed opinions to yourselves.

    • Nin

      Actually I’m insulin resistant as well…the doctor gives me medicine for it, I decided to diet on my own plan and went from 285 to 155 (I’m a 5’10” female) in about 8-9 months, that was about 3 years ago. I ate around 1200 a day and worked out. I gained about 25-30 lbs back since then due to side effects of a medication…but I’m now on another low calorie diet and in the last week I’ve lost around 5 lbs. It is possible for insulin resistant people accomplish this…I did it…and let me tell you, I didn’t think I ever could, I was so big for soooo long. I used the excuse that I could never do it because of my insulin resistance and hormone issues, but that just wasn’t true. Give it a good healthy try before you say it’s not possible.

    • Mama to twelve

      I must agree. I have lives for YEARS alternating dry or water only fasting days with 300-800 calories and am still 70 pounds overweight. I swear when the world ends in famine I will still have an ass and no
      Etabilism. I cannot force myself to eat more or more frequently. And yes I exercise several times a week. Tried the Michael Thurman diet (heLthy but ate too often), weightwatchers in the past (gained on that). And atkins (lost a little but then stopped for months). I guess i need to go to boot camp and do onsanity because “regular” exercise keeps my muscles in shape but does nothing foe the polar bear look. I quit…

      • Mama to twelve

        And i do a 3 week water fast every onths with only some temporary wt loss from that but it is good for my liver and kidneys

    • River

      Amen! People who don’t know what they are talking about *love* to flap their gums as loud as they can. It’s more complicated than calories in and out!!

      • Nin

        It’s really not. My insulin resistance and PCOS symptoms were almost fully relieved when I did low calorie diet.

  • david

    a zero calorie diet is impossible, it is called fasting, this cannot be sustained for very long. If one were to attempt it the longest they could last is about one month and the health risk go up exponentially each day it goes beyond only a few days. For instance as I mentioned with my write up, gall stones would be a risk after only a few days, and in a prolonged fast ekg changes can occur due to the hyponutremic state you would most likely be in.

  • Me

    It is not “impossible” to do a zero calorie diet. It’s called fasting. Get your facts straight.

  • Matt

    How do you, and what do you need to eat to put on weight? I will probably have to go on insulin soon. But weigh 52kg, 5 foot 6. Low carbs, low calories. How do I put on weight??

  • David

    Let me start by saying I am a nurse and by most accounts of my peers pretty well versed in nutrition. Vlcd diets are no fad, but the efficacy is just now being revisited after a few major studies by some very reputable universities. There was a great piece on Vlcd’s by vanderbilt university which watched for any EKG changes in at least 100, it may have been more, and after 3 months the two thirds that were able to comply had no EKG changes. They did say a few people had some, but were deemed unrelated to the diet and dismissed after they weren’t permanent, none of the changes were considered potentially fatal, minor changes such as prolonged qt intervals within normal limits were seen. The second study was conducted at Newcastle, it was a very small study with spectacular results, that woe need a larger group followed over a longer time to further verify the success. Diabetes, type 2, has never been considered to be permanent and is often controlled, if not reversible, if a patient is compliant with a healthy diet and exercise regimen. Very low calorie dieters with type 2 diabetes should Definitely see a physician or endocrinologist before start the diet, but the hypos can be avoided by properly titrating, that is backing off the dose for the newer lower caloric intake to avoid hypoglycemia. Anyone starting a new workout or diet regimen shod seek the advise of a physician who can adequately determine if your healthy enough, or overweight enough for a diet like this, Vlcd’s are great diets, but should only be attempted by those who are morbidly obese, that is 100 pounds overweight or more. Another key point to remember is the effects of Vlcd’s on the gall bladder, people who eat around 600 calories a day which is a true Vlcd, 600-800 calories daily, can get gall stones if they don’t eat between 7 and 15 grams of fat a day, the amount necessary for the gall bladder to contract. I hope this helps to dispell some rumors or myths.


    I am diabetic. i heard about 600cal diet and decided to try. and found after 10 days my blood sugar level became lower. and now i successfully complete 39days now my fbs is 79.3 and pps is 113.2. it is very difficult to live like this but surely u got a good result.

    • Bhanu

      Hi Sunil,

      I read your article can you please share your diet plan with me as i am also diabetteic and i am curious to know your diet plan.

  • anonymous

    Additionally, it all comes down capitalist regime – we are brainwashed into buying the products (i.e. food) that looks pretty and smells nice, – paying money to put fat, diabetes, disease, cancer onto our bodies – and then pay more money to take it away. It is keeping you docile while large corporations are raking in the profits. So please, think before you eat and there will be simply no reason to go on a low calorie diet in the first place..

  • Heather

    I am on phase 2 the VLCD can I eat cottage cheese?

  • Tom

    Don’t listen to one word of those who never tried the hcg diet because they are clueless in their starvation claims, as they don’t understand the body is breaking down fat stores which are providing thousands of calories on top of the 500 calories taken in daily. There’s no chance of starvation at all…just a bunch of idiotic fear mongering by people who read others idiotic fear mongering. The diet totally works. If its a fad, its one that’s been around for over 50 years. If it didn’t produce results, nobody would be using it. And as far as the FDA is concerned…LOL…please. these are the same people who hid the dangers of mammograms and the photocarcinogenic properties of vitamin A in sunscreens from the public for over 30 yrs. The same ones who approved aspartame. The same ones who approve rx drugs that gotta be yanked from circulation after the unwitting public finds out the hard way which side fx the FDA allowed the drug mfg to not report. Wake up. The reason the MDs and FDA don’t like the hcg diet is because it works, and its cheap. Instead these bums want you under their care (perpetual income stream) to swallow their deadly rx garbage, and to undergo lame unnecessary dangerous expensive surgical procedures like bariatric which runs in the neighbohood of $25k and even so, many put the weight back on! Talk about a ponzi scheme. But hey, nobody is stopping you from doing your so called healthy eating thing even though you might have screwed up metabolism from some past factor in which case none of that will amount to crap. Those of us who know better will follow a proven system developed 50 yrs ago when doctors still actually looked for cures instead of making millions on treatments designed to fail so patients must come back again and again at great cost. Your choice. But, don’t expect any of the informed to buy into your ignorant histrionics.

  • Shortterm

    These types of diets should be monitored, but anyone can fast. Your body can technically speaking can last at least 40 days without food, (People with higher BMIs for longer, hence why we have fat stores in the first place, in times of famine) as long as you are taking in enough fluids. Obviously before undertaking fasting you should do your research and talk with your doctor. I know several people that fast for religious reasons and offen. They are of normal body mass and are healthy.

  • Russell

    I have type 2 & was told it was for life. So foolishly I thought what the hell, just keep taking the pills.
    Now there seems to light at the end of the tunnel. If it works then I want to do the 600 cal diet especially if “it does what it says on the tin”.

    I’m fed up with popping pills & feeling knackered all the time.

    My GP said that he couldn’t/wouldn’t officially help as it was not recognised medical practice but I should contact Newcastle University myself. Easier said than done.
    If someone could please tell me how this should be done, maybe a proven diet, without making a mess of oneself I would be grateful.


  • 600 a day

    Im doing 600 cal a day, and now that ive found the right foods to eat it seems to work for me. I have half a low fat yogurt in the morning a lean cuisine at lunch and either soup or another lean cuisine with either a snack after lunch or dinner.. Im never starving and i like the food.. For me it was getting over the fast food addiction. But my life style helps too, i dont go out regularly.

  • Matthew

    You should read the study paper done by Newcastle University. 600 calorie diet CURES fatty liver in 1 week. Weight loss is continuous. Also cures diabetes. Read the study before you say, “Nah diabetes is for life this is stupid etc etc…”

    • Defren

      I have also done the 600 calorie Newcastle study. Over the course of the eight weeks I lost over 50lbs and have kept them off. I also have gone on to lose more. I was an obese T2 now my BMI is in the normal range. The Newcastle Diet works! My glucose levels are very low and very stable now. Anyone wanting to know more about this diet, just Google Newcastle Diet or Prof, Roy Taylor Newcastle University. Please don’t just laugh because it sounds crazy, this diet works for T2 diabetics.

  • Slow to lose

    People always say “You didn’t gain it in a month, you shouldn’t expect to lose it in a month.” But I did gain it that fast. After my 2nd baby, my thyroid went out and I gained 40 pounds the first month and 20 more the second and third. 80 pounds in 3 months before the doctor finally figured out the correct dosage. Then the dieting started, here is an example of one of them.

    For four months I went on a 1500 calorie per day diet making sure that I stayed under 25% of my calories from fat. (But I have to admit that most of my calories were from simple carbs, early 1990s) I joined Curves and worked out 4 to 6 days a week for 45 min per session. Each month they would weigh and measure me, and each month they would explain that muscle weighs more than fat so that should explain the weight gain or lack of weight loss, and that the other person who took my measurement last month must have measured wrong. One month I gained an inch on my waist while losing an inch on my breasts. I was definitely getting rounder. At the end of 4 months I had lost 4 pounds and gained 1.5 inches on my waist. I had dropped to 216 pounds.

    After 4 months of this, I had an uncontrollable craving and ate an entire German chocolate cake. I seriously considered purging but knew that’s the road to bulimia and didn’t want to take it. By the next day I had regained the entire 4 pounds and decided to just eat what I felt like eating and forget about the dieting for a while.

    I heard about the Atkins diet and decided to give it a try since I didn’t have to count calories and could eat as much protein as I wanted. I went on, felt great, and ate a lot of lean meat, eggs, and cheese every day, it had to have been at least 1500 calories. I dropped 24 pounds in 23 days. Then I ate one cookie and it was all over. The urge to eat more carbs was very strong and I figured I could try the diet again later when my schedule wasn’t so crazy. But in all future attempts I never lost the weight as fast and it gave me headaches and mood swings. It took about 1 year to regain all the weight I had lost.

    Tried a few diets here and there with limited success, but mostly just tried to limit my simple carbs and fats and follow good eating habits. Most days I averaged 1800 to 2200 calories, but it seemed that every week or two I would binge with a 10,000 calorie day. The longer I held off the binge, the bigger it was when I finally gave in.

    In 2006, a friend asked me to be her diet buddy on a juice diet and I was very skeptical. I would only get 800 to 1200 cal per day making it a VLCD and I had always heard they weren’t safe. But I was up to 247 pounds and getting pretty desparate. In 8 weeks I lost 55 pounds drinking fresh homemade juices and eating a small dinner with no simple carbs. I was hungry from time to time, but never the unmanageable cravings before the binges. Then the holidays hit and I started eating a bit too much. We moved and I lost contact with my diet buddy. In the next 4 years I regained 35 pounds back. I discovered that I need someone to be accountable to to really stick with it.

    That brings me to now. We moved back close to my diet buddy. She had cancer and had gained her weight back. At thanksgiving she was 197. She started the homeopathic HCG drops and dropped to 135 pounds and a size 6 by May. I started the HCG diet 11 days ago and I’m down 9 pounds. The coolest part is that it seems to mostly be coming off my waist instead of the breasts. I’m eating 500 calories per day and following the diet to the letter. I am a little hungry by mealtimes, but for the most part it isn’t too bad. I don’t really feel hungry, but I do feel empty. I’m not sure any other way to describe it. I’m not sure how hard it will be to adjust back to higher calories and if it will cause binges. But for now, I’m just glad to see progress again.

    My point in saying all this is to try to show that those of us who are obese are really trying to lose weight. Losing weight slowly with good diet habits is usually the FIRST thing tried. It does work for some people, but once your body is messed up due to Thyroid or diabetic problems it doesn’t work. The metabolisim changes so you hold on to every last pound and the urges increase to make sure you stay put. Diets that cut out processed sugars are the only ones that work to change the metabolism and reduce the feeling that you are starving. You may not agree with the safety of VLCDs, but obese people often decide they are worth the risk, because they are the only diets that actually work.

  • Shirley

    Diet is great,results great but if you are diabetic how do you prevent hypos and with a fatty liver you cannot lose weight quickly
    The new diabetic diet cure gives you 600 cal a day with above problems

  • so stupid

    If all your doing is drinking water, tea, and coffee than thats called starvation not a diet. you are not teaching yourself how to eat healthy and in the long run your just doing damage to yourself. when you do eventually eat (and i hope you do because otherwise that means death) you are going to gain all that weight you loss right back. If you do it right the way first you wont ever have to repeat even if it takes longer.

  • I

    If you gain muscle then you don’t have to worry about your metabolism – a pound of fat burns 4 cals a day and a pound of muscle burns 45. If you maintain the proper protein levels to support the amount of muscle you have you can maintain your resting metabolic rate.
    I do agree that anyone on this diet should be under the direction of a doctor and a nutritionist who can verify that you’re getting the proper nutrition (i.e. plan out meals that cover all your bases)

  • Shannon

    Technically 800-1000 is not VLCD.

    People on VLCD are called patients. I understand VLCD to be a medically supervised diet used to treat obesity. Your advice is stellar, but these people are not able to simply do what you suggest.

    To ThinToBe: I think that is sooo funny! :) Don’t know if you’re trying to be…

  • Wrong.

    Technically, it’s impossible to do a “0 calorie diet”.

    I wish people would just eat less & exercise more, instead of starving themselves on VLCDs at harming themselves.

  • scarednow

    I’m scared now. Been on a vlcd called protein sparing modified fast from a bariatric clinic 8 weeks at 800-1000 cal/day. Taking multivitamin and potasium. Lost 18 pounds (1 week lost no weight). Felt great. BUT am losing hair, and blood test came back with high liver enzymes and now I’m scared. I was told I had a fatty liver about 4 years ago, but I didn’t know what that meant and now I read that rapid weight loss with fatty liver can result in liver damage. Wish I’d known. Now I have to go for tests and I don’t know what.

    I was 100 pounds overweight – very obese. I heard somewhere that a lot of obese people have fatty livers.

    I wish I was making this up. I just want people to know what can happen. The diet is the only thing I did different (they did blood tests when I started 8 weeks ago at the clinic and liver enzymes were normal, so I know it has happened since the diet).

    P.S. I don’t drink alcohol at all.

    • Tiffany

      Did your liver enzymes go back to normal during the diet? Did they do any additional testing? I am currently in the same situation and wondering what to expect.

  • ThinToBe

    I do the 0 calorie diet. All I drink is water, coffee, and green tea. I lose 3 pounds the first day and 1-2 a day on the 6 days after. Just be careful not to binge, it ruins everything.

  • Wendy

    5 years ago I went from 117kg to 71.2 in 130 days using a vlcd. I have now had a baby and am up to 78.4 so I am back on the vlcd to loose the extra kilos. If you come off slowly it is easy to maintain. Plus the program I went on (LighterLife) deals with your relationship with food and shows you what your triggers are. I now live in South Africa and Lighterlife is not available here so I am still following their plan but using the Tony Ferguson soups/bar/shakes instead.
    VLCD are great for people who need to see big, quick results to stay motivated.

  • Chloe

    plus when I started eating more again, I did NOT gain the weight back :)

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