Another Discussion on Acceptable Caloric Deficits

songbyrdsweet

I'm not trying to steal Banks's thunder or anything hehe :laugh: I just stumbled across an article the other day that reminded me of one of my favorite ways to determine a maximum acceptable deficit.

http://www.mindandmuscle.net/mindandmuscle/print/printview.php?artID=35


Basically, it states that 1 lb of fat can provide you with 31 calories of energy per day. So, if you know your body fat percentage, you can estimate the maximum deficit that will maintain muscle mass.

For instance, if someone weighs 150 lbs and they are 20% body fat, they have 30 lbs of fat mass. That 30 lbs can supply them with 930 calories per day without a loss in muscle mass. If they need 2500 calories to maintain their weight, that deficit will allow them to eat 1570 calories a day while maintaining as much muscle mass as possible.

If that person tried for a 1000 calorie deficit, at the end of the week they would have used 490 calories from a non-fat source--skeletal muscle. Considering that there are only about 1800 calories in a lbs of muscle (4 cal/g of protein rather than 9cal/g of fat), you've just burnt through almost 1/3 of a lb of muscle.

This isn't entirely foolproof, and you do have to have at least an estimation of your body fat, but I find it to be very helpful since it takes lean muscle mass into account. Unfortunately, since our energy substrate needs change, we can't always use just fat for energy, and we won't always have enough glucose, so we can't save all of our muscle mass while we lose fat. And of course, these numbers are theoretical, because our bodies don't run on math. But it's still important to save as much as possible, and this definitely helps.

songbyrdsweet

I'm not trying to steal Banks's thunder or anything hehe :laugh: I just stumbled across an article the other day that reminded me of one of my favorite ways to determine a maximum acceptable deficit.

http://www.mindandmuscle.net/mindandmuscle/print/printview.php?artID=35


Basically, it states that 1 lb of fat can provide you with 31 calories of energy per day. So, if you know your body fat percentage, you can estimate the maximum deficit that will maintain muscle mass.

For instance, if someone weighs 150 lbs and they are 20% body fat, they have 30 lbs of fat mass. That 30 lbs can supply them with 930 calories per day without a loss in muscle mass. If they need 2500 calories to maintain their weight, that deficit will allow them to eat 1570 calories a day while maintaining as much muscle mass as possible.

If that person tried for a 1000 calorie deficit, at the end of the week they would have used 490 calories from a non-fat source--skeletal muscle. Considering that there are only about 1800 calories in a lbs of muscle (4 cal/g of protein rather than 9cal/g of fat), you've just burnt through almost 1/3 of a lb of muscle.

This isn't entirely foolproof, and you do have to have at least an estimation of your body fat, but I find it to be very helpful since it takes lean muscle mass into account. Unfortunately, since our energy substrate needs change, we can't always use just fat for energy, and we won't always have enough glucose, so we can't save all of our muscle mass while we lose fat. And of course, these numbers are theoretical, because our bodies don't run on math. But it's still important to save as much as possible, and this definitely helps.

Cowboy

Hey thanks. That's good stuff.
Cowboy

songbyrdsweet

Hey thanks. That's good stuff.
Cowboy

Glad you like it Your avatar is so cute! He's jammin on that guitar hehe :happy:

MontanaGirl

Thanks Song!! - Good stuff. More information = better informed choices

barracudamuscle

Dang well I guess I'm scraping the barrel then.....

244 x .26( scales estimate) = 63.44 Estimated amount of fat:grumble:

63.44 x 31 (calories fat provides) = 1966.64

Now where do I get my sustainment number? I did the metabolic tool feature and came up with 2187, now I know thats just the base number without any excercise or movment every day, Ill go with 2500?

So what this tells me besides the obvious that I'm 63 pounds of fat :frown: is 2500 - 1967= 530?

I know I messed something up, maybe 3000 is closer to my number? 1033 calories a day intake? MFP has me setup for 2 pounds a week and to eat 1710 a day, I really usually only eat about 1200 give or take a couple hundred. It has been working although Ive been stuck at 244 for about 3 days now compared to when I was lossing a pound a day if not more.

I am obviously missing something here but hey I'm just waking up to goto work so hopefully it will click although I am trying to sort it out up in my head right now. I guess brewing my own beer might not have been the best thing for my tummy,lol all those pounds are coming to hunt me!:laugh: :drinker:

banks1850

I'm not trying to steal Banks's thunder or anything hehe :laugh: I just stumbled across an article the other day that reminded me of one of my favorite ways to determine a maximum acceptable deficit.

http://www.mindandmuscle.net/mindandmuscle/print/printview.php?artID=35


Basically, it states that 1 lb of fat can provide you with 31 calories of energy per day. So, if you know your body fat percentage, you can estimate the maximum deficit that will maintain muscle mass.

For instance, if someone weighs 150 lbs and they are 20% body fat, they have 30 lbs of fat mass. That 30 lbs can supply them with 930 calories per day without a loss in muscle mass. If they need 2500 calories to maintain their weight, that deficit will allow them to eat 1570 calories a day while maintaining as much muscle mass as possible.

If that person tried for a 1000 calorie deficit, at the end of the week they would have used 490 calories from a non-fat source--skeletal muscle. Considering that there are only about 1800 calories in a lbs of muscle (4 cal/g of protein rather than 9cal/g of fat), you've just burnt through almost 1/3 of a lb of muscle.

This isn't entirely foolproof, and you do have to have at least an estimation of your body fat, but I find it to be very helpful since it takes lean muscle mass into account. Unfortunately, since our energy substrate needs change, we can't always use just fat for energy, and we won't always have enough glucose, so we can't save all of our muscle mass while we lose fat. And of course, these numbers are theoretical, because our bodies don't run on math. But it's still important to save as much as possible, and this definitely helps.

Damn it SBS! You took all my mojo

good post!

lessertess

Great article. I thought this must be the case but have had a time finding the information. It appears the study was done exclusively on men. I wonder how much the calorie/pound (31) would change for women? I would guess there is a difference?!

songbyrdsweet

Dang well I guess I'm scraping the barrel then.....

244 x .26( scales estimate) = 63.44 Estimated amount of fat:grumble:

63.44 x 31 (calories fat provides) = 1966.64

Now where do I get my sustainment number? I did the metabolic tool feature and came up with 2187, now I know thats just the base number without any excercise or movment every day, Ill go with 2500?

So what this tells me besides the obvious that I'm 63 pounds of fat :frown: is 2500 - 1967= 530?

I know I messed something up, maybe 3000 is closer to my number? 1033 calories a day intake? MFP has me setup for 2 pounds a week and to eat 1710 a day, I really usually only eat about 1200 give or take a couple hundred. It has been working although Ive been stuck at 244 for about 3 days now compared to when I was lossing a pound a day if not more.

I am obviously missing something here but hey I'm just waking up to goto work so hopefully it will click although I am trying to sort it out up in my head right now. I guess brewing my own beer might not have been the best thing for my tummy,lol all those pounds are coming to hunt me!:laugh: :drinker:

Well like I said...it's not foolproof. I should've mentioned that there is a cutoff at which the equation is no longer applicable. In your case, a 1000 calorie deficit would be acceptable. Obviously you can't live on 500 calories a day without a doc's supervision, and we don't want you to do that!

So as a disclaimer, if you get a # that is higher than 1000, that just means you could get away with a 1000 calorie deficit.

songbyrdsweet

Great article. I thought this must be the case but have had a time finding the information. It appears the study was done exclusively on men. I wonder how much the calorie/pound (31) would change for women? I would guess there is a difference?!

Our fat is made of the same stuff as men's fat, just in different places hehe :laugh: The substrate we use most frequently may be different since I have seen some evidence that women use glucose more frequently than fat for some of the functions that take place to maintain homeostasis, but our fat still has the same number of calories per gram and still provides the same amount of energy as any other fat, whether it's from peanut butter or an animal or the fat that a man carries.

barracudamuscle

Well said song,

I knew I was the one to put the * in the system. 500 calories a day? Thats a big challenge,hmm... I could imagine it would only last about 3 days until I couldn't handle it. I wouldn't want to take the risk doing that while flying thats for sure. It would consist of water, iceberg lettuce, mustard, and some other empty calorie idea.

I think I'm pretty close the that number of 1000 calories though, I ate about 1200 yesterday. Its working but I'm always looking to tweak it a little more. I have to say I feel so stupid when it comes to all of this, which is very eye opening. I know plenty of engineering, mechanics, physics but body stuff, yea... about that. I think I'll just refer you to my friends at mfp.com ask for song or banks, and everyone else whose name is slipping my mind (pretty much everyone!) Thanks for opening my eyes up to all of this, the more I know the healthier I can live my life in the future.

beep

for bunny

FatDancer

Thanks Songbyrd! There was a girl looking for advice on this subject yesterday, or day before

BabyGrlRae

Thanks Songbyrd! There was a girl looking for advice on this subject yesterday, or day before

It was me. This helped clear things up and in the end I decided to increase my calories (oh darn, right?) and only do the 500 cal deficit/day. Thinking I may have been pushing a little too much.

Thanks for the help!

beep

beep

Bump

yellow_pepper

Great post, Songbyrd.

frenchfoodlover

bumper sticker

songbyrdsweet

bumping this up again

FatDancer

Thanks for bumping this post Songbyrd!

I read the post and the article...got my body fat % via the tape measure method...got stuck on the math and was unable to calculate...sorry 'bout that.

It said to calculate your body fat percentage in lbs.

How many lbs is a percent of bodyfat?

I'm sure it was explaned in your post or the article...I read and re-read and just couldn't figure that out.

My Son's teachers always told him, "don't let your mom help you with your math homework".

Thank's again Songbyrd...all of your posts are most helpful!

songbyrdsweet

Thanks for bumping this post Songbyrd!

I read the post and the article...got my body fat % via the tape measure method...got stuck on the math and was unable to calculate...sorry 'bout that.

It said to calculate your body fat percentage in lbs.

How many lbs is a percent of bodyfat?

I'm sure it was explaned in your post or the article...I read and re-read and just couldn't figure that out.

My Son's teachers always told him, "don't let your mom help you with your math homework".

Thank's again Songbyrd...all of your posts are most helpful!

I'm sorry if my math was confusing!! To find your lbs of body fat, you have to multiply your body weight by the percentage of fat, in decimals. So for instance, if you are 150 lbs with 25% body fat:

150 X .25 = 37.5 lbs.

So you would have 37.5 lbs of fat. Multiply that by 31 and you get 1162. However, we know not to go above a 1000 calorie deficit, so we'd bump that down to 1000 calories as an acceptable deficit. I hope that helps!

IndigoElectron

Apart from getting it checked by a doctor or at a gym, how do you estimate your body fat?

songbyrdsweet

Apart from getting it checked by a doctor or at a gym, how do you estimate your body fat?

There are calipers and bioimpedance hand-helds you can order online to use at home by yourself. Or, you can use girth measurements and use a military conversion, although I haven't seen the best accuracy with those.

FatDancer

Thanks for breaking it down for me Songbyrd...now I get it!

Here's the site where I found the tape measure method of determining bodyfat % for those that don't have access to calipers, etc.:

http://www.healthcentral.com/cholesterol/home-body-fat-test-2774-143.html