Harm in huge deficit for mordibly obese?

IPOARM recommends 20-30% under your TDEE for those who are morbidly obese, but only for a short period of time, I believe.

azulvioleta6 wrote: »

christinev297 wrote: »

I'm 5"8, 140lbs ,sedentary. And trying to stick to 1200 calories is incredibly hard for me.
You could try it, and if you get the urge to binge because you're so hungry, just bump your calories back up to a more manageable deficit.
Wishing you the very best of luck :flowerforyou:

I am tall, very active (often burn 1500+ calories in a day) and I ate around 1200 calories for a couple of years without a problem.

I've recently started to eat a little more, but I don't NEED to in order to be comfortable or to get decent nutrition. I've got some unique issues, including an extremely low BMR due to health problems...but it CAN be done.

OP, I think that you have to try it for yourself to see whether or not it works and is reasonable for you.

The fact that you have a health issues today and an extremely low BMR may be related to your low calorie intake of several years. Please note - I am not saying it is the case, but a possibility as metabolic issues are known to arise for people that are highly active and also restrict calories a lot.

Of course, could be totally unrelated too.

If I were you, I would see a doctor and do it that way, so then you could loose more under doctors supervision.

yarwell wrote: »

ditsyblond17 wrote: »

I'm 320. 5'7 and sedentary. My BMR is 2,200.

Katch-McArdle formula would put your BMR at 1600 based on lean body mass - the purely weight based ones are off their scale at 320 lbs.

There's no specific issue eating below your BMR as calories are supplied from fat reserves and if you're sedentary eating below BMR is mathematically inevitable if you want to lose even 1 lb/week.

I'm not convinced, yet. Got a reference?

Revised HB ...

http://www.ncbi.nlm.nih.gov/pubmed/11817239

yarwell wrote: »

doesn't include the Katch-McArdle or any body fat considerations ?

Includes Cunningham. Which is the Katch McArdle, just adjusted for RMR. It also includes Nelson. Both are LBM equations and Nelson has BF on top of LBM.

CONCLUSION:
In patients with obesity class II and III the equation of Harris-Benedict predicted the average BMR with acceptable precision for clinical use and was better fitting than most of the currently available predictive equations for basal metabolic rate (BMR). However, the recalculated version (by Roza et al.) was more accurate and should therefore be used instead of the original equation: BMR (men) = 88.362 + 4.799 x (length) + 13.397 x (weight) - 5.677 x (age); BMR (women) = 447.593 + 3.098 x (length) + 9.247 x (weight) - 4.330 x (age). The Nelson equation, including not only LBM but FM as additional predictor, was the best predicting equation ([108 LBM + 16.9 FM]0.239). Harris-Benedict equation had sufficient precision also in extreme obese subjects with a body weight > or = 120 kg, so there is no need for adaptation.

Edit: not that it's a major point - these equations still have a Standard Deviation of 10-15% I'd prefer to calculate from my own eating habits and MFP data.

If only someone had developed a tool to do that...



Oh, wait (see first link in my profile).

ditsyblond17 wrote: »

Thank you all so much. It is starting to make a bit more sense. I was using Harry Benedict formula and that says my BMR is a TON higher than what is given for lean body mass. No wonder I got to this weight. Technically it says I need to eat 1,600 to maintain, but I easily eat 1,000+ a day more before I was conscious of it. Even if I've learned nothing else so far, I've learned it's incredible the amount of food our eyes thinks our stomachs need.

I don't know what went wrong there but that's no way right.

I weigh 127lb and maintain at 1800 plus without exercise, add exercise in and I get to eat back 400-600 per hour depending on what I'm doing. You'd burn even more than that because of your weight.

From Scooby's calculator I put in that you're 320 5'7" female age 25 and desk job with no exercise.

Your BMR (basal metabolic rate-lying around in a coma rate) is 2054 to maintain, your TDEE (total daily energy expenditure, just bumbling along doing day to day things) is 2465.

I really trust this calculator, and so do others.

Try losing 2lbs a week (7000 cals) by being in a deficit of 1000 per day.

Your Magic number is......1465.

Very do-able!

Then to help all us readers, please weigh yourself every day and average out every 7 to test your weight loss is working. The fist couple of weeks you'll lose lots more because of water loss, then it should go to cruise for a while.

Remember to recalculate your Tdee every 10lb lost, and if you add exercise.

Best of luck!

christinev297 wrote: »

You're lucky azulviolet. I totally struggle
I was wondering if it would be even harder for OP because she weighs so much more??

It might be, but it might be easier. I would find 1200 impossible now that I'm close to goal weight (like you), but found it easy when I first started and was in the 200s (I'm only 5'3). Bodies are weird.

SMR (MJ/day)=1.89+0.105FFM (kg) from a population similar to the OP http://www.nature.com/ijo/journal/v24/n6/full/0801230a.html unfortunately doesn't report individual data despite only 8 subjects. About 1880 for the OP.

Using Nelson I get 1827, Rosa 1687. Estimated %BF from BMI etc. All well short of the standard 2200 prediction which is where I was coming from.

With so much to lose, 3 pounds a week would be okay. As you lose weight though and have less to lose, that's not going to work.

Zedeff wrote: »

Lots of people telling you that aggressive goals and deficits are unsustainable. These people are just projecting their own issues onto you. If YOU can maintain an aggressive deficit, then it doesn't matter that they couldn't.

Bonneville salt flats came to mind. The swamp at the end is tricky though.