TDEE/BMR Help

Bump :flowerforyou:

I side with the camp who say your deficit should come from your TDEE, and not fall below your BMR.

Same. I eat at TDEE - 20%, with my activity level set to sedentary since I have a desk job. I log my exercise using my HRM, and then eat back most, if not all, of the calories burned through workouts.

I've been wondering about doing it this way, too. Problem is, my numbers vary greatly with each calculator I find. It's so confusing

Hey, heybales! Your spreadsheet is the one that's making the most sense to me! Thank you for putting that together. There are still a few things I don't understand, but I'm reading all the threads here and am learning more each day.

We all walk into playing around with this stuff blind because we're all physically different, with different daily lives and not many of us can afford to be hooked up to more accurate metabolic measuring machines.

Don't get hung up on numbers. Just pick a place to start, do it for a month, weigh in and see what happened. Then adjust accordingly.

A good guesstimate starting point for you is probably TDEE - 20%... in your case about 1900 cals. Start there and just roll with it... it's all trial and error.

No less than your BMR please.

MFP calculates your goal using rudimentary math. The energy value of 1 pound of fat = 3500 calories. In order to burn 1 pound of fat, you need a deficit (burn more than you eat) of 3500 calories. In a week, that would be a deficit of 500 calories per day (3500 cals / 7 days = 500 cals/day).

SO! If you tell MFP that you want to lose 1 pound a week, it will tell you to eat 500 calories less than its calculation of your TDEE each day. If MFP thinks you need to eat 2000 calories, it tells you to eat 1500.

If you tell MFP that you want to lose 2 pounds a week, it will tell you to eat 1000 calories less than your TDEE per day ( 1000 * 3500 = 7000 which is the energy value of two pounds of fat). If MFP thinks you need to eat 2000 calories, it tells you to eat 1,000.

What happens if you tell MFP you want to lose three pounds, or four pounds, per week? It tells you to eat a DEFICIT of 1500 calories, or 2000 calories per day. It's "dumb math" very quickly tells you to starve yourself.

Start at your TDEE - that's what you burn in a day. Anything less than that is a caloric deficit and will make your body burn fat.

If your BMR is 2000, then don't eat 1500. That will help.

No less than your BMR please.

MFP calculates your goal using rudimentary math. The energy value of 1 pound of fat = 3500 calories. In order to burn 1 pound of fat, you need a deficit (burn more than you eat) of 3500 calories. In a week, that would be a deficit of 500 calories per day (3500 cals / 7 days = 500 cals/day).

SO! If you tell MFP that you want to lose 1 pound a week, it will tell you to eat 500 calories less than its calculation of your TDEE each day. If MFP thinks you need to eat 2000 calories, it tells you to eat 1500.

If you tell MFP that you want to lose 2 pounds a week, it will tell you to eat 1000 calories less than your TDEE per day ( 1000 * 3500 = 7000 which is the energy value of two pounds of fat). If MFP thinks you need to eat 2000 calories, it tells you to eat 1,000.

What happens if you tell MFP you want to lose three pounds, or four pounds, per week? It tells you to eat a DEFICIT of 1500 calories, or 2000 calories per day. It's "dumb math" very quickly tells you to starve yourself.

Start at your TDEE - that's what you burn in a day. Anything less than that is a caloric deficit and will make your body burn fat.

bump..thanks for sharing.

Your TDEE includes all of your exercise. If it doesn't, you need to increase the multiplier. It includes working out one day and not working out the next. It is an average.

Your body needs X number of calories to function. It is unrelated to your BMR. You can and many do function for long periods of time eating less then their BMR. It is a myth. It can be an issue for those that are lean but for the obese and highly overweight it isn't something to worry about. Fat doesn't need to be fed. Think of it this way a woman that weights 120 pounds and at her ideal weight may have a BMR of 1500 calories (made up number) An obese person that weighs 220 pounds, BMR may well be 2000 calories. (same age/height) Let's agree that their LBM is roughly the same, (yes the obese person is likely to have a slightly higher LBM). The obese person can easily function on the same calories as the 120 pound person. Like I said you don't have to feed the fat. Your body will take the calories from your fat sources and turn it into most everything your body needs to function.

And these two people, for their BMR about the same because of the same LBM (actually, fat is metabolically active, just a whole lot less than LBM, but I'll play along), this also means we aren't talking about an inflated BMR estimate, what happens to their daily activity once they start moving?

Obviously the heavier is going to expend way more energy and calories on everything moving more mass.

So there is a bigger impact on daily activity to what is burned.
So the little lady eating her 1800 calories (1500 BMR +300) is leaving plenty for her metabolism to use after some is supplied to daily activity, the bigger lady eating the same 1800 is not by a long shot.

In addition, while the energy expended in the BMR, which is energy expended on the cells, does ultimately come from fat if no recent meals are being used, the fat cells are actually having energy expended on themselves too. Energy out, some wasted as heat for processing, energy in, some wasted as heat for chemical reactions.

Since we don't have little perpetual motion machines in our cells, there is a lower limit where the body will lower the different levels of metabolism, BMR a tad, RMR a tad, then cause the body to lower the Non-Exercise movements to save some calories for the BMR it can't adjust as much.

Since you'll find it about impossible to find that line where the body decides it's going to do that, based on it's current stress level, what it's seen before, genetics, ect, it is best to stop at BMR.

Unless you can be part of a study and have your RMR measured and confirmed it hasn't dropped beyond what the weight loss would cause.

But sadly even there, got a gal on higher calorie to break plateau, that she got from being in a study, lost great weight during the study, was given here stats showing she dropped RMR more than loss of weight would have required, and they said good day.
I don't recall how long she was on a plateau - but said she'd never recommend anyone to be in a study unless they knew ahead of time exactly what was going to happen.

I've also noticed on many of these studies that do maintain a decent RMR with strength training, when they care to comment on their selection of study participants, they are of course overweight, but interestingly state not involved in a weight loss program before. I'm finding that more interesting lately. How bad does yo-yo dieting effect those results if they used yo-yo dieters?

I'm not arguing that stopping your cut at BMR isn't a good idea. I was saying that, being under BMR is unhealthy is a myth or at best misunderstood. The problem is that people become so confused by the information overload. They take what they have heard, even though most of it is wrong, and take it as gospel. What is known and proven changes more often then people realize. So the gentleman said that eating under BMR is bad. It isn't necessarily so. It isn't something I would recommend for a long period of time, but people do fast all the time. Some of the longest living and healthiest people fast regularly. (I'm not one of them)

Oh yeah, beyond the fasting examples as totally valid that short term is no problem, how about the concern that if you don't eat 3 squares a day, or is it 6, that your body starts breaking down muscle!

Yes, exaggeration of a valid concern applied to a different setting might protect you, but also have you causing more stress than needed, probably killing any positive in your actions.

Meal frequency matters not. Eat once or 20 times. Doesn't make any difference at all. The 6 meals a day myth has been exposed. (Yes if you are bulking for muscle growth it may still hold some relevance.) Eat how best satisfies you, just don't go over your goal. If you like to eat 6 times great. 3 times great. Once a day, great.

Or even once annually.

As far as eating below BMR or not goes, above is a good set-it-and-forget-it approach. IF, zig-zagging, etc is a little too complicated to a mindset that is saying "if I'm not losing, I should cut more calories".
I've seen five or ten people write about sleep eating. Inevitably folks have their "cheat days" where they overcompensate for the abusive dieting. Eventually they crump and binge and then decide that dieting is too hard and they can't do it - - even though the irony is that they were trying so much harder and making it so much worse than it ever needed to be.

So BMR is a fair cut off, I think.