Confused about FitBit calorie numbers

[turksandcaicos]

So I'm supposed to have a 250 calorie deficit in order to lose 0.5 lbs. per week. I've just started using the food log on the app and I'm a bit confused. For example, yesterday it says 1801 calories in and 1952 calories out and that I was 99 calories over for the day. But how can I be over if it says I took less calories in than out? In addition, the difference between the two number is 151. Help! 

[SunsetRunner · Accepted solution]

It sounds like you were over on the allotted calories in for the day for your half pound a week goal. You had a calorie deficit of 151 calories. To lose a half pound a week your daily calorie deficit would be 250.

[JimC_99]

Be careful with believing the calories burned reported by the fitbit - I have been tracking the data from my fitbit since early April and the raw numbers reported are between 40 to 60% off (high in my case).  based on food logging and calories burned reported by the fitbit, I should have lost 70 lbs and have actually lost 52 lbs (which is still great, just different from the reported numbers).  I seem to track better with the calculator from NIH with a light activity setting of 1.3, which based on the calories logged data is within 5% of the actual weight loss.

[Dominique]

---

@turksandcaicos wrote:

So I'm supposed to have a 250 calorie deficit in order to lose 0.5 lbs. per week. 

---

It’s not uncommon for humans to underestimate their intake and for activity trackers to overestimate energy expenditure. If the human underestimates their intake by 250 calories and the tracker overestimates energy expenditure by 250 calories, a planned deficit of 500 calories will turn into no actual deficit at all. 

If you’re new to tracking your food and to using your Fitbit, you should probably shoot for a higher planned deficit (e.g. 500 or 750), understanding that the real deficit will be lower (as @JimC_99 observed when comparing his actual weight loss to the predicted one). Once you have been tracking everything (intake, activity and bodyweight) for some time, you can make adjustments, if needed.

[turksandcaicos]

Thank you! I see your point and yes, I'm new to food tracking/calories burned. I'll set my goal to 1 lb./week then. 

[turksandcaicos]

Wow - 52 lbs. is great - congrats!!! But yes, it should say 70 lbs. if that's what the reported numbers say. Thanks for the tip. 

[turksandcaicos]

a-ha! Now I see how they got the numbers - OMG - thank you!!!!!