Fitbit calculating BMR based on months of not wearing it

[chpalmer24]

For months I left my Fitbit sitting on a counter charging and I’m now getting back to using it.

Based on zero steps and zero activity it was saying I was burning 1960 calories. 

My problem is now that I’m wearing my Fitbit it tells me I burn about 2,800 or 2,900 calories a day but it keeps my BMR at the 1960. So when setting a 1,000 calorie deficit, it says I can only eat about 960 calories a day. For a 6 foot 200lb man who is somewhat active...

is there a way to either delete out all the days of “false” 1900 calorie burned days or force Fitbit to change my BMR? If it adjusts on its own how long does that take?

[JohnnyRow]

I think you might be misunderstanding BMR calories.  These are calories burned, not calories eaten.  If Fitbit says you burn 2900 calories a day, for a 1000 calorie deficit, you would still eat 1900 calories.  Where BMR comes in is that, of the 2900 calories your burned, 1960 were burned just by being alive, and 940 were calories that you burned from activity in addition to your BMR.

Here is some info on BMR.  The BMR (basal metabolic rate) calories are what you are always burning just by being alive.

Your BMR is credited every hour of every day, even when you are not wearing the tracker.  This makes sense because you are burning those calories, no matter what.

Your BMR estimate I believe is based on your height, weight, age, and gender.  It changes as your weight, and age, change.  You can google "BMR calculator" to find various calculations of BMR, and you will find they are all very close to what Fitbit uses.

[chpalmer24]

That’s my issue. At the end of the day after burning 2800 calories according to my Fitbit it still says my calorie goal is 960... I ate about 1200 calories and it says I’m 200 over my goal. It’s calculating my calorie goal based just on my BMR and not adjusting up based on additional activity. So it’s subtracting 1000 calories from 1960 and telling me that’s my goal even if I’m actually burning far more calories.

[JohnnyRow]

It sounds to me that your issue is not really with the BMR value, but rather how the calories allowed to be eaten and calories remaining is calculated.

So I'll bow out of this thread as I have no experience with  food tracking.

But here is an article from the Fitbit Blog about calorie allowance that many have found helpful.

https://blog.fitbit.com/fitbit-calories-in-vs-out/