Bmr, calories and weight loss.

goldyray1 · April 2021

I would like to create a scenario just to see if I am understanding.
60 year old female
175 pounds. Goal is 135 pounds
BMR is 1500
Calories allowed each day to consume 1200
If each day I burn 2500 calories (pretend with no exercise/lazy person)
I eat 1200 calories a day.
How much does that give me a day to go towards the goal of burning 3500 calories a week to equal a pound of fat loss.
This is totally a scenario. Given this information, is this enough to lose at least a pound a week? Is this number I am looking for considered the 'net' calories?
Ideally exercise would go along with this but this is just so I understand the process.
Thank you.

lgfrie · April 2021

You're not burning 2500 calories per day. Given your stats, your "break even" - the calories you could eat and neither gain nor lose weight - is approximately 1700 per day. To verify this for yourself, you should go to TDEEcalculator.net, a site that many people use here and is quite accurate for most.

Burning 1700 calories per day, and eating 1200, you will lose 500 calories worth of fat per day or - voila - 1 pound per week (since 500 x 7 = 3500). So this would likely work out perfectly for you.

It's basically that simple.

You have a couple of numbers in your post that aren't helping. First, BMR is irrelevant to weight loss. BMR is the # of calories you'd burn if you were in a coma, but you're not in a coma; the number that matters is your maintenance calories, also called break-even, and also called TDEE, and in your case around 1700. Second, the 2500 is not related to anything. The only way you would burn 2500 per day is if you were doing a LOT of exercise. Again, TDEEcalculator.net says your maintenance calories is around 1700, nowhere near 2500.

Here's how net calories work:

If you eat 1200 calories, your net calories are 1200. If you then do 100 calories worth of exercise, your net calories would be 1100. Net calories = the calories you eat minus the calories you earn working out. Net calories is only relevant if you are doing workouts. The idea is that you should eat your exercise calories so that your net calories doesn't go below 1200. In other words, if you eat 1200 and then do a 200 calorie walk, you're supposed to eat the 200, because otherwise your net calories would be 1000, which is too low, and is unhealthy.

PAV8888 · April 2021

As per above for the gist of things.

To be more pedantic

I won't say that 2500 is *absolutely impossible* for a 60yo 175lb female; just **extremely** implausible and unlikely given that she goes on to state: "pretend with no exercise/lazy person".

If she were, instead, saying "pretend I'm a very active on the go" person, then the 2500 would, all of a sudden, become much more likely.

Also, assuming the 1500 BMR figure was a correct estimate (I don't see a height stat above, so I can't double check), the initial sedentary TDEE estimate would be ~1850. Thus eating ~1350 net Calories should result in about 1lb loss a week

sijomial · April 2021

From your other post your Garmin is estimating you burn a total of around 2000 cals so in theory (if your Garmin and your food logging are both accurate) eating 1500 will result in 500 cals a day deficit and 1lb of weight loss a week.

Why do you think estimating your BMR is helpful to you?

You seem determined to complicate the process rather than just pick a tool which does the number crunching for you.
Simplify rather than complicate would be my advice!

Either use your Garmin or use MyFitnessPal or use a TDEE calculator but don't mix and match - when you have a number of weeks of consistency you will know if you are on the right track.

nanastaci2020 · April 2021

Your body uses energy (calories as fuel) in 3 ways:

BMR - this is the effort your body puts into keeping you alive. For your heart, lungs, brain and other organ daily functions. For your body to maintain its temperature, digest food, circulate oxygen and such.

Normal daily activity - this is energy spent to move your body thru its normal day. Hobbies, home life, job. *This is why MFP asks about your activity level in the guided setup** A person who is on their feet constantly during their day will use more energy than someone who is sitting at a desk all day, for example. It will be a % of your BMR. Such as a sedentary, doesn't move much during the day person may burn 15% of their BMR in activity daily. Someone more active may burn 25% and someone VERY active may burn 35%.

MFP uses those two: BMR and normal daily activity to give your calorie goal.

Third is cardio. Your body burns at a higher rate when you are doing cardio because you are moving multiple major muscle groups for an extended period of time. This one is a little awkward, as its hard to know exactly and its easy to overestimate.

MFP expects that if you exercise, you will log the exercise calories and eat them in addition to your regular calorie goal. THis is where 'net' calories come in.

If your BMR is 1500 then without exercise, you probably burn 1800-2200 depending on how active your day is. For sake of example, lets say you tell MFP that you're sedentary/not active and MFP expects you to burn 1800 daily. You put in a rate of loss of 1 pound per week, so MFP tells you to eat 1300. Because 1800 - 500 = 1300. Lets say today you log 1250 calories in, log 250 calories exercise. Remember. MFP's target of 1300 is BEFORE exercise, so your day would look like 1300 target -1250 logged - 250 exercise = 1000 net and show you having 300 calories 'left' to eat. If you don't feel the 250 is accurate (maybe you think its inflated) then you could of course consider to eat just a portion of the exercise calories.

heybales · April 2021

goldyray1 wrote: »

I would like to create a scenario just to see if I am understanding.
60 year old female
175 pounds. Goal is 135 pounds
BMR is 1500
Calories allowed each day to consume 1200
If each day I burn 2500 calories (pretend with no exercise/lazy person)
I eat 1200 calories a day.
How much does that give me a day to go towards the goal of burning 3500 calories a week to equal a pound of fat loss.
This is totally a scenario. Given this information, is this enough to lose at least a pound a week? Is this number I am looking for considered the 'net' calories?
Ideally exercise would go along with this but this is just so I understand the process.
Thank you.

Yes understanding is needed - the formulation of the questions shows you need more.

So you would be burning 2500, and eating 1200.

Think body is happy eating less than 50% of what it needs to maintain desired stasis (yes it desires that)?

If this is MFP that estimated a daily burn of 2500 - then you would NEVER be given an eating goal by MFP of 1200, because 2 lbs weekly, or 1000 cal deficit, is the max it gives no matter how foolish that might be for someone.

If MFP estimated daily burn 2500, it would give 1500 eating goal if you selected 2 lb weekly with 1000 cal deficit.
2500 daily burn - 1500 eaten = 1000 deficit

BMR is meaningless except to calculate MFP what Activity Level must have been selected - in your scenario it was told above Active. (2500/1500=1.66)

1000 cal deficit daily x 7 days = 7000 cal weekly deficit = 2 lb weekly.

Obviously the numbers you gave are bigger deficit - you should be able to do the math now and see that clearly you are losing way more than 1 lb weekly - if you really ate that much, and if you really burned that much in reality.

Regarding NET calories - you are NOT looking for any other number because you are already given it - in your scenario the 1200, for what MFP would actually say the 1500.

You said no exercise, therefore your NET eating goal and base eating goal would always be the same.

Let's pretend 1500 was really your base eating goal, safe to get in enough nutrients so you didn't harm your body, enough calories so your body didn't start adapting and making this harder and stressed out and possibly damaged.
And that was based on pretty active lifestyle with no exercise, just always going.
Those 1500 calories provided for base metabolism just living and enough fuel for keeping active so not wanting to sleep all the time.
But it forced the body to burn more fat because you did burn 2500 on those typical days.

Now you go exercise hard for 1.5 hour and burn 500 calories purely for the extra movement, this is not energy used for metabolism or anything else, just the exercise.
So from the 1500 calories you would normally eat - 500 was used just for the exercise - not repairing cells, not growing hair or nails, not repairing from the exercise, not for your other daily activity.
You now left 1000 for rest of those functions where the body really wanted 1500 before you'd get negative effects, if you don't eat more.
Your body wants 500 more for the basic functions and daily activity.

Now the 1500 if that is all you ate, leaves NET 1000 eaten for basic body functions. Your exercise sucked off 500 calories just for that - your body wants 500 more to not be stressed and do what it needs to do.
Your NET eating goal of 1500 now needs 500 more eaten if you only ate the 1500, leaving only 1000 for normal daily functions.

But you burned in total 2500 + 500 exercise = 3000.
You will eat in total 1500 + 500 exercise = 2000.
You have the same 1000 deficit.
Your NET goal was still 1500.

goldyray1 · April 2021

i UNDERSTAND!!!!! Thank you so much for taking the time and using my scenario so that I could understand. I never could understand the reasoning behind eating back your exercise calories. I always thought that it would hold you back from losing pounds. I do see now. I did choose the 2 pound a week with MFP. Thank you again!!!!

lgfrie · April 2021

It's OK to set a goal of two pounds a week, but here's a suggestion. It's actually pretty difficult to keep up that pace of weight loss for any but the most trivial amounts of time, e.g. a couple/few weeks. It really becomes a slog to keep up with the 2 lbs/week goal, unless one is starting from a very obese level, which you are not. Few people manage to keep up that pace, and most who push themselves that hard end up regaining the weight. So go for it if you want, but keep in mind that one pound a week is a big success, and a half pound some weeks is OK too. Learning to be happy with 1 lb/week and not seeing it as falling short, or as evidence that "things aren't working", is really, really important, even if you've set a goal of 2 lbs/week.

I dieted for six months at 2 pounds per week, so I know it can be done, but it was very draining and I wouldn't repeat it. My revised goal of 1 lb per week is the reason I'm still at it and haven't regained the weight.

Bmr, calories and weight loss.

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