BMR as calorie goal?

I was using what my maintenance calories would be at my goal weight at one point. Really any number between what MFP gives you and your maintenance calories will work. I personally feel like hell on the tiny number the boards and MFP recommend as a reasonable calorie goal for me.

MarkusDarwath wrote: »

jennybearlv wrote: »

I was using what my maintenance calories would be at my goal weight at one point.

I used to use that as my base and subtract 300. It doesn't work for me any more because by body fat % got so high that my current maintenance is actually -less- than maintenance for my goal weight and composition. I'm at a size that I should be able to safely lose 2+ pounds per week, but I can't manage to cut that many calories from my diet, so I absolutely have to use exercise to create a deficit now.

As to the OP, I would not use BMR as a calorie target unless your activity and exercise are going to be minimal. BMR is literally what you need to maintain if you are lying still and not doing anything... unless you are talking about BMR with the activity factor figured in. In that case, yes, you can probably go with that number and have a separate exercise routine... assuming you have your non-exercise activity matched to the correct activity level multiplier.

The problem with don't eat below your BMR is many obese people will lose at a discouragingly slow rate. In my case a googled BMR calculator gives me 1734 calories. I have 80 pounds to lose so advice on the boards would be okay with me setting MFP to lose 2 pounds a week. This puts my calories at 1200. Without exercise I would have to set MFP to lose a half pound a week to eat above my BMR. Does that sound like a reasonable rate of loss for someone with 80 pounds to lose?

The numbers are different so I don't know how this applies to the OP and losing 28 pounds, but it won't work for some people.

jennybearlv wrote: »

The problem with don't eat below your BMR is many obese people will lose at a discouragingly slow rate. In my case a googled BMR calculator gives me 1734 calories. I have 80 pounds to lose so advice on the boards would be okay with me setting MFP to lose 2 pounds a week. This puts my calories at 1200. Without exercise I would have to set MFP to lose a half pound a week to eat above my BMR. Does that sound like a reasonable rate of loss for someone with 80 pounds to lose?

The question here is, would that 1734 be a -strict- BMR, or does it include the activity level adjustment? Your strict BMR, again, is the calories you need to maintain your weight if you were literally laying in bed 24/7 doing nothing... basically in a coma.

Another potential issue with online BMR calculators is the question of which formula they use. The Harris-Benedict equation is very popular, and accurate for most, but it doesn't factor in actual body fat percentage, which introduces a tendency to lose accuracy when applied to much heavier than average people. If the unusual mass comes from muscle than the calculated BMR tends to be low for that individual. In a very obese person there's a tendency to overestimate BMR.
For those of us closer to the statistical extremes the Katch-Mcardle equation is often more accurate. And it's the same for men or women since it uses actual body composition in the calculation.

BMR (men and women) = 370 + (21.6 × lean mass in kilograms)

In my case, at 285 pounds and over 38% body fat, my lean mass rounds to about 175 pounds, which rounds to 79kg. 370 + (21.6 x 79) = 370 + 1706.4 = 2076.4 calories for BMR. Applying a sedentary activity factor (1.2) brings my TDEE up to 2491.68. I'm probably actually a touch more active than sedentary, but not up to lightly active so I round the TDEE off to 2500 calories per day. With those numbers, using TDEE to set up a loss of 2 lb per week, or BMR to calculate a 1 lb per week loss would both put me at around 1500 calories for a daily target.
Even though MFP will accept that as a goal without flagging the starvation warning at me, I know from personal experience that even 2200 calories is too hard for me to stick with over the long term. There's not a chance in heck I'd be successful if I tried to drop my calories below BMR. That is why I say that I need to create my calorie deficit via exercise.
Aside from the motivational difficulty in eating below one's lean mass based BMR and expecting to actually go about daily activities, I suspect that in such a deficit one is also at much greater risk of losing a high proportion of weight in lean mass. The health value of losing weight can be undercut pretty badly if it happens without much change in body fat percentage.
The good news for us who are obese is that every bit of movement/exercise burns significantly more calories than it does for someone of a more normal weight. Just by pure physics a man who weighs 250 pounds will burn almost half again as many calories as a 150 pound man per distance run or walked.

kljfo wrote: »

sijomial wrote: »

MFP doesn't "default" - you are influencing the number by the rate of loss and activity setting you input.
Your calorie goal on here is also plus exercise.

Really don't see the point in having and using a Fitbit if you don't at least trial the numbers it gives you (minus an appropriate, not excessive deficit) and then adjust if necessary after a period of weeks.

And no I wouldn't ever have used my BMR as a goal - it's far too far away from my TDEE.

Hi there - when I say default - i meant after inputting my 'influencing figures in' - it comes up with 1270 (to be exact). I have trialled the numbers of my Fitbit, I've had it since September.

Basically was trying to get a sense check based on the numbers I did provide from my fitbit. Maybe it's just a mind thing but losing 2 stone in 7 months (1Lb per week) feels like an incredibly looooonnnnnng time.

That said, when I do cut to 1200 calories a week, I have seen 5-8lb loses but I also feel horrid - so I'm just looking for a middle ground I guess. Something that's going to keep me motivated and feeling well, but equally something that means I can lose 2stone in about 4 months.


This morning I set up a spreadsheet (geeky but hey!) i compared my calories burned vs calories consumed as entered into MFP - i was sort of surprised. My deficit this week was 4,400 calories - so maybe that's it. It's just crunching numbers all week to get to the deficit that feels right and adjusting as I go :-)

thanks everyone for your input!xx

Even considering your "aim for the stars" goal of 3 stone, 2 lbs a week is aggressive. Unless you're over 200 lbs, 2 lbs or more per week is risking muscle mass, miserableness, and honestly just generally hitting the wall hard.

The diet industry has made us think it's normal for people to lose 5 lbs a week. It's not, unless you are very obese or don't care about your health.

If it was me, I would set my goal to 1 lb per week, and start off eating back half of my exercise cals from the Fitbit. Give it a few weeks. If you feel good and you're averaging 1 -1.5 lbs per week, your golden. If not tweak your numbers up or down as you go. Most people who lose weight aggressively tend to not be happy with how they look once they get to goal. Patience is a virtue Good luck

One could do it as a test and if your sticking to it and you dont see weight loss over a decent time period, I would have to say it is not the best policy. Cut the intake calories back down to the 1250 and wait and see if you see results.

kljfo wrote: »

thanks for the response.

I have 2 stone to lose as a minimum to get back to where I usually am and slap bang in the middle of my healthy weight range, 3 stone if I'm going for "lovely and slim" looking. (I'm not a body builder or anything like that - the BMI/healthy weight guides works well as a guide for me)

MFP gave me - 1270 calories at a 2lb per week weight loss and 1770 for a 1lb per week weight loss

I think it's more the numbers on my fitbit that's got me thinking....If it's correct and I am burning 2,800 calories on average per day - then a 1200 calorie diet is way too low - that's creating a daily deficit of 1600 calories.

But I've read that fitbits can be quite a bit out when it comes to calories burned. If say the fitbit is over-estimating, I could be burning as little as 2200 calories and if I use MFP's 1800 calories 1lb per week loss - it feels a bit 'tight',

Wait, what? Am I understanding right: You have 3 stone - 42 pounds - to lose; you are targeting 2 pounds a week; . . . and if you eat at that calorie goal you lose 5-8 pounds a week?

That's not reasonable. At 42 pounds to go, 1 to (at most) 1.5 pounds a week is a more reasonable starting goal, unless you're very large/tall. Try that goal for about 6 weeks (if you're a premenopausal woman), and see what your average loss is for the latter 4 weeks. If it's more than a pound and a half - or if you feel fatigued or weak, then or earlier - eat more.

Everything is estimates. Your Fitbit's estimate is probably slightly more likely to be accurate than MFP. If it says 2800, I'd recommend eating 2050 (750 daily deficit = 1.5 pounds loss) for 6 weeks, tracking eating meticulously, and see what happens.

The worst that can happen is that you'll lose more slowly than you prefer. It's unlikely that you'll fail to lose at all. Adjust eating after 6 weeks as needed. 1250 sounds way to low. For most people, BMR is also too low.