Using Basal Metabolic Rate (BMR) to Track Diet Progress

ericGold15

Hi Fitters,

There are lots of ways to track progress, but after a week using the program I settled on a method that works well for me and perhaps for others so I thought to share:

Background:
BMR is the amount of calories a body needs in 24 hours to sleep and hang out in front of the TV. The BMR varies by sex, age, height and weight. Here is a nice calculator.

I set my daily calorie goal to my BMR. Then through the day the Fitness program takes into account food and exercise and shows the NET calories as 'calories remaining' in big blue numbers on the home page, or as 'net calories' on the summary page.

Presto! Instant insight into how the diet is going:

• 0 Calories remaining at the end of the day: nothing gained, nothing lost
• Calories remaining: Weight is going down
• Calories in excess: Weight is going up

A pound is 4000 Calories; a Kg is 9000. The week summary is really helpful here. E.g., if I am 6000 Calories negative for the week I have burned 1.5 pounds of fat assuming my muscle is stable.

Note that I have not tried to account for the non-exercise activity. For me it is pretty low -- around 100 to 150 Calories a day. I prefer to ignore that amount and collect it on the scale

CyberTone

​Your estimate of a 4000 Calorie per week deficit to lose one pound of weight is not the generally accepted value of 3500 Calories per week (or 500 Calories per day), which is what MFP uses. Also, the calculator you linked in your post uses an estimate of a 3500 Calorie per week deficit to lose one pound of weight in its calculations.

Reference:
myfitnesspal.desk.com/customer/portal/articles/1599931-nutrition-101-calories

ericGold15

<<shrug>>
Use whatever number you please; after a while the scale will tell the tale.

Fwiw, packaged fat in the human body *is* 9 Cal/gram.

ericGold15

Oops, I ended the post too soon.
There are 2.2 US pounds in one Kg, so

9000/2.2 = 4090 Cal/pound. I round off for easy arithmetic in my head.

lemmie177

I'd be really interested in seeing how closely your change in weight/week tracks with your calculated deficit. Would you be willing to share your results so far?

ericGold15

lemmie177 wrote: »

I'd be really interested in seeing how closely your change in weight/week tracks with your calculated deficit. Would you be willing to share your results so far?

Hi Lemmie,

There is nothing special in my log but I can certainly open it to anybody interested.

The weight correlation for now is poor. In part this is due to starting the diet a few weeks before starting to use MFT; in part because I guessed at my starting weight; in part because I spend time between two homes and use two scales; and finally, (I suspect) because my body muscle and body water are not stable.

I actually just bought a new scale that measures fat percentage. With all the caveats that go along with that measurement not being accurate, etc, I'm hoping that the trend will be precise enough to show a tight correlation with calorie deficit.

sheldonklein

Unless I'm misunderstanding your post, you misunderstand the relationship between BMR and weight loss. Simply stated, there is no relationship. You lose or gain weight based on whether you are under or over your TDEE. BMR is a factor in calculating TDEE, but otherwise it is irrelevant to weight loss.

ericGold15

CyberTone wrote: »

​Your estimate of a 4000 Calorie per week deficit to lose one pound of weight is not the generally accepted value of 3500 Calories per week]

Here is a bit of the science behind the numbers: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2376744/

As I said, pick a number

ericGold15

Cybertone,

I gave some more thought to your comment and realize that we are mostly having a semantic misunderstanding, although my wording has not been accurate.

My interest is in losing stored fat -- triglycerides. It takes 9000 Cal energy deficit per Kg
Adipose tissue, on the other hand, has upwards of 10% water bound to the triglycerides. So 9000 Cal deficit will lead to ~ 1.1 Kg weight loss of adipose tissue presuming no muscle mass was lost.

DavPul

ericGold15 wrote: »

Oops, I ended the post too soon.
There are 2.2 US pounds in one Kg, so

9000/2.2 = 4090 Cal/pound. I round off for easy arithmetic in my head.

Dude, you are making this about 19 steps to complicated for no particular reason at all

SoCalSwimmerDude

DavPul wrote: »

ericGold15 wrote: »

Oops, I ended the post too soon.
There are 2.2 US pounds in one Kg, so

9000/2.2 = 4090 Cal/pound. I round off for easy arithmetic in my head.

Dude, you are making this about 19 steps to complicated for no particular reason at all

Yup.

But he seems the scientific type, so whatever works.

ericGold15

sheldonklein wrote: »

You lose or gain weight based on whether you are under or over your TDEE.

I'll guess that TDEE is shorthand for 'total daily energy expenditure' ?

If so, do you agree that a good approximation of that number is equal to
Exercise + BMR ?
And that your NET energy lost or gain for the day is Exercise + BMR - food ?

We report food and exercise; the missing variable is BMR.

kk_inprogress

I guess I'm missing the point here. Why guesstimate a weight loss when you can just get on a scale?

Also TDEE=BMR+activity level+exercise. You missed activity level since BMR is the amount you would need to maintain weight supine in bed all day.

Edited for content.

PikaKnight

ericGold15 wrote: »

sheldonklein wrote: »

You lose or gain weight based on whether you are under or over your TDEE.

I'll guess that TDEE is shorthand for 'total daily energy expenditure' ?

If so, do you agree that a good approximation of that number is equal to
Exercise + BMR ?
And that your NET energy lost or gain for the day is Exercise + BMR - food ?

We report food and exercise; the missing variable is BMR.

Waaaa????

ericGold15

kkenseth wrote: »

I guess I'm missing the point here. Why guesstimate a weight loss when you can just get on a scale?

Also TDEE=BMR+activity level+exercise-food.

To estimate *fat* loss

Understood about TDEE. In the OP I mentioned that I personally ignore activity level since it is pretty sedentary. YMMV

kk_inprogress

ericGold15 wrote: »

kkenseth wrote: »

I guess I'm missing the point here. Why guesstimate a weight loss when you can just get on a scale?

Also TDEE=BMR+activity level+exercise-food.

To estimate *fat* loss

Understood about TDEE. In the OP I mentioned that I personally ignore activity level since it is pretty sedentary. YMMV

Still doesn't change the base definition of TDEE, though. You can use whatever you'd like, but can't claim the definition changes because you don't count it that way.

Sued0nim

sheldonklein wrote: »

Unless I'm misunderstanding your post, you misunderstand the relationship between BMR and weight loss. Simply stated, there is no relationship. You lose or gain weight based on whether you are under or over your TDEE. BMR is a factor in calculating TDEE, but otherwise it is irrelevant to weight loss.

This ^^

Sued0nim

ericGold15 wrote: »

sheldonklein wrote: »

You lose or gain weight based on whether you are under or over your TDEE.

I'll guess that TDEE is shorthand for 'total daily energy expenditure' ?

If so, do you agree that a good approximation of that number is equal to
Exercise + BMR ?
And that your NET energy lost or gain for the day is Exercise + BMR - food ?

We report food and exercise; the missing variable is BMR.

You're giving advice and you're "guessing" what TDEE means? ...wow...just...wow!

BMR+activity level= NEAT
NEAT+purposeful exercise =TDEE
TDEE-calories =weight loss
Weight loss=water weight loss+fat loss+LBM loss

20yearsyounger

OP, I understand where you are going with this as I did it myself. However, I used the BMR at my goal weight. That way I didnt have to keep changing it. Once i hit my goal weight, I just upped my calories to maintain weight as my activity is all over the place.

ericGold15

20yearsyounger wrote: »

OP, I understand where you are going with this as I did it myself. However, I used the BMR at my goal weight.

I set my BMR as my calorie goal. Is that what you meant ?

20yearsyounger

ericGold15 wrote: »

20yearsyounger wrote: »

OP, I understand where you are going with this as I did it myself. However, I used the BMR at my goal weight.

I set my BMR as my calorie goal. Is that what you meant ?

As an example. I started at 180 and wanted to get to 165. So I put 165 in your calculator and that was what I used as my calorie goal.

_Terrapin_

ericGold15 wrote: »

sheldonklein wrote: »

You lose or gain weight based on whether you are under or over your TDEE.

I'll guess that TDEE is shorthand for 'total daily energy expenditure' ?

If so, do you agree that a good approximation of that number is equal to
Exercise + BMR ?
And that your NET energy lost or gain for the day is Exercise + BMR - food ?

We report food and exercise; the missing variable is BMR.

So your profile indicates your a physician. NEAT is missing above and TEF. So, TDEE=EAT(exercise) + NEAT(non exercise and/or your daily job) + TEF + BMR. NEAT is what most people can change and do, some add EAT(exercise) and some try to impact their TEF through changes in their diet. And, for me, if I set my calorie goal as my BMR I'd be at a daily deficit of about 1,000 calories daily. My preference is to lose weight slowly and learn habits to sustain the lose. If I want to be miserable in the process and increase the likelihood of putting the weight back on I'd attempt your method. Good luck.

DavPul

ericGold15 wrote: »

20yearsyounger wrote: »

OP, I understand where you are going with this as I did it myself. However, I used the BMR at my goal weight.

I set my BMR as my calorie goal. Is that what you meant ?

so you perform your daily activities while in a coma?

ericGold15

DavPul wrote: »

ericGold15 wrote: »

20yearsyounger wrote: »

OP, I understand where you are going with this as I did it myself. However, I used the BMR at my goal weight.

I set my BMR as my calorie goal. Is that what you meant ?

so you perform your daily activities while in a coma?

Almost
My work is equivalent to a desk job, and I am generally pretty sedentary at home if I am not exercising. If my daily activities were considerably more I would add them to my daily calorie goal.

lithezebra

I love to overthink my weight loss too! It's probably because I miss doing thermodynamics problems. I've tried eating at around my BMR, and after two days all I feel like doing is staying in bed. Perhaps it's because my activity level is fairly high. I've set my calorie goal at a deficit of about 1750 kcal/week taking my daily activity and my exercise into account. Because bodies are weird, I lost no weight at all for about 3 weeks, and suddenly dropped 2.5 pounds in one week, which all averages out to a bit better than I'd expected.

If you're sedentary, I can't recommend finding non-exercise ways to be more active highly enough. I made my desk into a standing desk, shortly before I suddenly started losing weight. Also, although I didn't use this calculator for my total daily energy expenditure, it's great for getting a picture of how much time you spend sitting, sleeping, walking, and engaging in strenuous exercise. Good luck!
http://www.health-calc.com/diet/energy-expenditure-advanced

ericGold15

_Terrapin_ wrote: »

If I want to be miserable in the process and increase the likelihood of putting the weight back on I'd attempt your method. Good luck.

I am not suggesting a diet routine. The use of BMR as the daily calorie goal is only an accounting trick to make it easy to to see the net calorie change over a period of time.

If your routine daily activities are substantial, it makes sense to me to add them to the daily calorie goal.

ericGold15

lithezebra wrote: »

I've tried eating at around my BMR, and after two days all I feel like doing is staying in bed. Perhaps it's because my activity level is fairly high. I've set my calorie goal at a deficit of about 1750 kcal/week taking my daily activity and my exercise into account. Because bodies are weird, I lost no weight at all for about 3 weeks, and suddenly dropped 2.5 pounds in one week, which all averages out to a bit better than I'd expected.

I am NOT advocating that people eat an amount equal to their BMR. Actually, I'm not advocating anything.

I am saying that putting the daily calorie goal equal to the BMR makes it easy to track net calories for people who are fairly sedentary outside of exercise. If routine daily activities are more than sedentary then it makes sense to add them to the daily calorie goal and then gain the same ease of net calorie tracking.

Your story rings a bell. I have been the same weight for two weeks now despite a net calorie deficit of some 15k Calories. I presume the difference is water accumulation although I really don't know. Perhaps I am rehydrating my oh so neglected muscle mass. In any case I can see the adipose tissue shrink by the week so I am not concerned.

I look forward to the correction

Thanks for your comment

fyoung1111

Attempting to do this math to six decimal points of precision is a fools errand. BMR is a guess. TDEE is a guess. Calorie consumption is a guess. Useful? You bet. Worth considering the contribution of TEF? Absolutely not.

After all, it takes a few thousand calories over or under to even move the needle. My calculated MSJ BMR is 1513. MFP pads your BMR based on your subjective assessment of your activity level (set to sedentary in my case) and calls the result "calories burned from normal daily activity"—1,709. Garmin computes my MSJ BMR based on an out of date weight and adds a 20% premium to that to arrive at what they call my BMR of 1,807. Which one is right? None of them are right. They are based on different assumptions and used in different ways. Does it matter? Not so much. I presume that, if I eat more than about 12,000 calories in a week, I better be doing some intentional exercise to burn those calories up and then some. I still have 5 lbs. to lose .

Thanks for the NBCI link Eric. It appears to be that the classic Forbes equation (3,500 kcal/pound) works great for obese people and, frankly, most thin people could care less about any of this.

ericGold15

fyoung1111 wrote: »

Thanks for the NBCI link Eric. It appears to be that the classic Forbes equation (3,500 kcal/pound) works great for obese people and, frankly, most thin people could care less about any of this.

Thanks for the excellent comment.

Regarding the Forbes equation, my suspicion is that it works well for obese people because they are losing weight by reducing food (calorie) intake. Then when they burn 9000 Calories they remove some 1.1 Kg adipose tissue as an average. Weight reduction with a large (and perhaps increasing) exercise component is going to be more complicated and non-linear due to fluid shifts into the muscle compartment. If it were possible to track *fat* (as opposed to adipose tissue) we would find that a Kg loss requires 9000 Cal energy deficit.

This is somewhat of an academic point for people who want to lose weight, but it is of interest to people who focus on fat reduction.

ericGold15

Fyoung1111,
I concur about 'TEF.' Forget it.

Much better places to look for the unrecognized variation in our accounting are the methods used to determine food constituents and amounts, and their bio-availability.

fyoung1111

You will probably find this interesting: http://www.cell.com/cell-metabolism/fulltext/S1550-4131(15)00350-2