Why is it safe for a super morbidly obese person to eat 800 cals a day?

I'm super confused by this! Usually the heavier/taller you are the more calories you can eat and still lose weight aslong as their is a deficit, but why is it when someone is super morbidly obese its not uncommon or unhealthy according to Doctors to put them on a diet of 800 - 1000 calories?

But if you are just obese its not safe to be on a 1000 calorie diet and they recommend something closer to 1200- 1600 (for a female)

Any thoughts?
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Replies

  • AimiAutumn
    AimiAutumn Posts: 22 Member
    tomteboda wrote: »
    It's not safe. It's dangerous. However, exceptionally heavy individuals are at very high risk and their weight also poses acute danger. So it's a tradeoff... The risk of a crash diet vs the risk of sudden death. Physicians monitor their progress and vitals if they recommend this.

    That makes a lot of sense :o Thanks!
  • RobD520
    RobD520 Posts: 420 Member
    Agreed , I see it all the time... my guess ( just a guess) is that the Doc feels they are at a breaking point and need to immediately make changes to prevent serious health issues.

    This is basically the reason...
  • erinc5
    erinc5 Posts: 329 Member
    edited June 2016
    I agree with what others have said. When you get to the point of being 500+ lbs you have to weigh the risks of being that big with the risks of going on a low calorie diet. I believe perhaps that the medical community has figured that it is actually safer to get down to a healthier weight faster. The super morbidly obese do lose weight on these diets, but they also suffer other effects. Many people who go on these VLCD (800 cals per day) either through supervision alone or as a result of WLS will experience hair loss, kidney stones, dental issues - all related to the fact that they are nutritionally deficient while on these diets. It's a balancing act the bigger you get.
  • kommodevaran
    kommodevaran Posts: 17,890 Member
    I have a follow-up to this: Does a super morbidly obese lose - fat - faster on a 800 calories diet than on - say - a 2000 calories diet? What about that 1% of total body weight per week/31 calories per pound of fat before you start to cannibalize muscle rule of thumb?
  • kommodevaran
    kommodevaran Posts: 17,890 Member
    I have a follow-up to this: Does a super morbidly obese lose - fat - faster on a 800 calories diet than on - say - a 2000 calories diet? What about that 1% of total body weight per week/31 calories per pound of fat before you start to cannibalize muscle rule of thumb?

    If you're talking about general fat loss, of course they would lose more fat eating 800 calories vs. 2000. If you're talking about fat to muscle ratio, they would probably maintain more muscle mass on 2000 calories. But when you're morbidly obese you have more serious health issues to worry about than cannibalizing muscle tissue. As someone said above the risks of being morbidly obese often outweigh the risks of a low calorie diet.

    Ah, I see - I took it to mean that the 1% (or whatever) was all the fat that can be lost, not that any loss beyond that will be (just) an increasing muscle:fat ratio. It makes sense. Thank you.
  • SugarySweetheart
    SugarySweetheart Posts: 154 Member
    AimiAutumn wrote: »
    I'm super confused by this! Usually the heavier/taller you are the more calories you can eat and still lose weight aslong as their is a deficit, but why is it when someone is super morbidly obese its not uncommon or unhealthy according to Doctors to put them on a diet of 800 - 1000 calories?

    But if you are just obese its not safe to be on a 1000 calorie diet and they recommend something closer to 1200- 1600 (for a female)

    Any thoughts?

    Usually a defecit that low (800 - 1000 cal diet) would suggest the person has had Weight Loss Surgery.
  • lilltessiiie
    lilltessiiie Posts: 57 Member
    yarwell wrote: »
    I have a follow-up to this: Does a super morbidly obese lose - fat - faster on a 800 calories diet than on - say - a 2000 calories diet? What about that 1% of total body weight per week/31 calories per pound of fat before you start to cannibalize muscle rule of thumb?

    Yes they lose faster. If they have 100 lbs of fat they can supply 3100 cals a day and 100 lbs of fat would be about 220 lbs woman.

    Here's a graph of 25% deficit (CR) vs 800 kcal LCD :-

    m_joc60035f2.png


    (PS the VLCD intervention was up to a 15% weight loss then maintenance)

    I would like to read that study. Yarwell, do you know the title and when and were it was published?
  • PAV8888
    PAV8888 Posts: 14,238 Member
    That would be before Fat Free Mass is affected. I.e. when you're trying to selectively optimise for fat loss only. https://www.ncbi.nlm.nih.gov/pubmed/15615615
  • BiggDaddy58
    BiggDaddy58 Posts: 406 Member
    edited October 2016
    My own view is that a morbidly obese person can handle a very low calorie diet for longer than you think without serious damage.

    I'd say of course, check with your Doctor first, but in my own case..I was 57 years old, 5' 11" and weighed 308 pounds.

    I put myself on a 1200 calorie a day diet. (I stayed between 1200-1300 for a good 3 months) This is way too low for a man, but you can do it. I imagine a woman, needing less calories than a man, could do 800-1000 depending on their stats, safely, for a short period of time.

    My Doctor never batted an eye when I told him what I was doing. Everyone is different, as are Doctors.

  • ahoy_m8
    ahoy_m8 Posts: 3,053 Member
    PAV8888 wrote: »
    That would be before Fat Free Mass is affected. I.e. when you're trying to selectively optimise for fat loss only. https://www.ncbi.nlm.nih.gov/pubmed/15615615

    Thank you so much for that!
  • ahoy_m8
    ahoy_m8 Posts: 3,053 Member
    edited October 2016
    daniip_la wrote: »
    I'm 6'0" and weigh 298lbs. I'd rather stay this size than go on an 800kcal/day diet.

    I get lightheaded and dizzy if I have a 1500kcal deficit for a few days, I think a 2000+ kcal deficit for more than a day or two would kill me. Or I would kill someone.

    The 30kcal/lb fat rule of thumb focuses on one aspect only--how much energy one's fat stores can provide. It does not address the multitude of other physiological systems that let you function or feel normal, e.g. hormones that regulate blood sugar to prevent lightheadedness or passing out. I did note above, apologies for the repeat, that just because a big deficit is possible doesn't necessarily make it safe.
  • heybales
    heybales Posts: 18,842 Member
    edited October 2016
    Here's a study of not obese but the BMI category of overweight, and same effects. Study is link in this post.

    http://www.myfitnesspal.com/blog/heybales/view/reduced-metabolism-tdee-beyond-expected-from-weight-loss-616251

    The other interesting thing about almost every one of those studies - the people tested were NOT any ANY weight loss mode for prior 6-12 months, no attempts to lose weight.

    Many times that's what the Dr is working with too for their extreme diets for short periods.
  • heybales
    heybales Posts: 18,842 Member
    ahoy_m8 wrote: »
    PAV8888 wrote: »
    That would be before Fat Free Mass is affected. I.e. when you're trying to selectively optimise for fat loss only. https://www.ncbi.nlm.nih.gov/pubmed/15615615

    Thank you so much for that!

    And if you read the actual "study" - it wasn't. It was a theorizing on other studies (mainly 1) and the results they got from that study - that study wasn't actually after that info of max fat loss. That was obtained by playing with formulas from the results.
  • mangrothian
    mangrothian Posts: 1,351 Member
    ahoy_m8 wrote: »
    daniip_la wrote: »
    I'm 6'0" and weigh 298lbs. I'd rather stay this size than go on an 800kcal/day diet.

    I get lightheaded and dizzy if I have a 1500kcal deficit for a few days, I think a 2000+ kcal deficit for more than a day or two would kill me. Or I would kill someone.

    The 30kcal/lb fat rule of thumb focuses on one aspect only--how much energy one's fat stores can provide. It does not address the multitude of other physiological systems that let you function or feel normal, e.g. hormones that regulate blood sugar to prevent lightheadedness or passing out. I did note above, apologies for the repeat, that just because a big deficit is possible doesn't necessarily make it safe.

    You're right. Creating a deficit that large isn't safe; or at least doing it without supervision it isn't. Under strict medical supervision, it does make it safe-er (this is part of the reason you're not allowed to promote doing a VLCD on mfp, as it isn't something that should be encouraged by someone who isn't a medical professional). But I think some of the health problems some people with obesity have are much riskier than their doctor helping them with a plan like this.

    My husband was put on one for 4-6 weeks as a way to help reduce chronic knee and back pain from a workplace injury. He's 5'10 and started at 125kg. There was no way I would have every allowed him to even try an 800Cal diet if it wasn't for the fact that he has a GP, nutritionist (the qualifications are a little bit more credible for nutritionists in AUS), psychologist and physiologist all watching over him whilst he does it.

    He's hangry all the time and he's tired. I plan the one non-shake meal he has daily very carefully to make he gets enough protein and fibre, and has something that will fill him up at the end of the day.In my husband's mind, for all that he doesn't want to have to do it, to decrease the pain that he's in on a daily basis, the end justifies the means even if it isn't the safest way to begin losing weight. It's also a hell of a lot safer then his body slowly becoming addicted to opiate-type painkillers.
  • Aaron_K123
    Aaron_K123 Posts: 7,122 Member
    I believe its a risk assessment. What does more damage. 12 weeks of an overly restricted diet that is likely going to lose you lean muscle and do you some harm or 12 weeks of remaining morbidly obese, given that there is a reason its called "morbidly" obese. I don't think its because it somehow isn't also damaging to them to eat that little, its just less damaging than being that overweight in the estimation of some doctors.
  • PAV8888
    PAV8888 Posts: 14,238 Member
    heybales wrote: »
    Here's a study of not obese but the BMI category of overweight, and same effects. Study is link in this post.

    http://www.myfitnesspal.com/blog/heybales/view/reduced-metabolism-tdee-beyond-expected-from-weight-loss-616251

    The other interesting thing about almost every one of those studies - the people tested were NOT any ANY weight loss mode for prior 6-12 months, no attempts to lose weight.

    Many times that's what the Dr is working with too for their extreme diets for short periods.

    Yes. But the majority of people on the boards these days don't believe that adaptive thermogenesis is "significant" or of "concern" that should be actively avoided.
  • singingflutelady
    singingflutelady Posts: 8,736 Member
    edited October 2016
    PAV8888 wrote: »
    heybales wrote: »
    Here's a study of not obese but the BMI category of overweight, and same effects. Study is link in this post.

    http://www.myfitnesspal.com/blog/heybales/view/reduced-metabolism-tdee-beyond-expected-from-weight-loss-616251

    The other interesting thing about almost every one of those studies - the people tested were NOT any ANY weight loss mode for prior 6-12 months, no attempts to lose weight.

    Many times that's what the Dr is working with too for their extreme diets for short periods.

    Yes. But the majority of people on the boards these days don't believe that adaptive thermogenesis is "significant" or of "concern" that should be actively avoided.
    sorry wrong thread
  • Sued0nim
    Sued0nim Posts: 17,456 Member
    Is "super" morbidly obese a term now?

    Wasn't morbidly obese enough?