BMR - question

Jentrin03

Hello!

Not sure if this is the right place to ask this.... My BMR is 1409. Am I suppose to eat 1409 calories or 1200 calories plus whatever I burn from exercising?

Need help understanding this.

jram70

Yes that is the amount of calories you need to "survive" so you should eat them. Really you should use the calculator under the goals section to determine how many calories to eat.

TrainingWithTonya

It depends on what is actually being calculated for your BMR. A lot of sites use the calories burned from your normal daily activity + the actual BMR and call it BMR or RMR. Everything I've been taught is that you add up all of the calories you burn daily, which would be BMR + normal daily activity not counting exercise + exercise calories to get the Total Daily Energy Expenditure. You shouldn't eat below your actual BMR, but you can eat up to 20% less then your TDEE. Anything more then 20% less then TDEE puts you at risk for slowing the metabolism by being too low in intake. Unfortunately, for ease of calculation sites like MFP tend to use 500 or 1000 calories per day deficit instead of the no more then 20% deficit. That's why some people end up with a calorie recommendation below their BMR. That's also why some people quit seeing results as they get closer to their goal or don't see results if they are only trying to lose a little bit of weight.

If your actual BMR is 1409 and you are sedentary then you multiply your BMR by the activity factor of 1.2 for sedentary to get an estimate of calories from BMR + normal daily activity not counting exercise. (That's basically multiplying by 120% so you are adding 20% without having to multiply and then add, but if it is confusing then you can multiply by 0.2 and add the total to BMR to get the BMR + normal daily activity not counting exercise.) That would give you an estimate of 1691 of BMR + normal daily activity not counting exercise. If you then exercise and work off 300 calories you add that to the 1691 to get 1991 calories for TDEE. You can then multiply the TDEE by 80% to get the minimum calories you should eat to lose weight. 1991 x 0.8 = 1593 calories per day. IF that is the case for you, then 1200 calories would be too low, but the 1593 would still be above your BMR and would allow almost 400 calories of a deficit, so not quite a pound a week of loss if you go by the 3500 calories per pound loss. (Unfortunately, that's not the only factor for weight loss, but it is much easier for people to calculate so we use it.) Yes, you will lose weight slower because you aren't having as big a deficit, but you won't risk slowing your metabolism to do it so you are less likely to gain it back if you start to eat a little more later.


ETA: Those activity factors go up based on more activity. Sedentary is 1.2, Lightly Active is 1.4, Moderately Active is 1.5, Extremely active is 1.7, and Athlete is 1.9.