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How accurate is Fitbit?
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justjenny
Posts: 529 Member
I just received a Fitbit Inspire HR as a gift. I have worn it non stop for 4 days and it says that I am burning almost 2000 calories a day. I have been eating roughly a 1200 calorie meal plan for forever and never really seem to lose weight. If I happen to go over my calories, I gain everything I lost back and it takes 3 days to get back to where I was. I just realized I may have been in starvation mode. Is that possible? I started upping my calories based on the Fitbit. The first two days I was gaining, and on the third day I dropped. I am hoping to see a continued decline over the weeks. I just wonder if I am on the right track. Anyone else have any related experience with Fitbit?
I forgot to mention that I am pretty much non stop all day. I never seem to stop moving, and I work out for about 30 minutes in the morning. Mostly HIIT, and some toning. Also when I figure out my TDEE on an online calculator, it has me between 1400-1500 calories a day.
I forgot to mention that I am pretty much non stop all day. I never seem to stop moving, and I work out for about 30 minutes in the morning. Mostly HIIT, and some toning. Also when I figure out my TDEE on an online calculator, it has me between 1400-1500 calories a day.
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Replies
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I have found my Fitbit (Charge 2) to be very accurate. That said, some people have found that it overestimates their calories burnt. The only way to really tell is to track your results over time.
If you have been eating 1,200 calories "forever" and not losing weight, then something else is probably going on. It's not "starvation mode," because that isn't a thing. While it's a bad idea for your health and wellbeing to eat much less than you need, people in a deficit will lose weight. Your body can't run for free. If you aren't losing weight on a low calorie diet (and 1,200 calories is very low), my first thought is that you might be accidentally eating more than you think you are. There are a set of common logging errors that may lead to this, but I can't see your diary to offer anything more concrete.6 -
are you weighing your food on a food scale? carefully choosing entires in MFP? this is usually where the issue is when people are not losing weight.5
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Are you confusing BMR with TDEE? 1400-1500 is probably your BMR.4
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Get yourself a weight trend app (or start using a web site like trendweight.com connected to a freely available fitbit.com account for data entry).
Establish your weight trend over a period of time that includes at least one monthly cycle. Are you trending up or trending down? How fast?
Adjust by eating a LITTLE BIT LESS or a LITTLE BIT MORE based on your NET CALORIES (calories in - calories out)
On the face of it you are neither logging your food accurately, nor had you been logging your calories out accurately given that based on your description a TDEE of 2000 Cal is quite likely.
You're neither the first nor last person to do so and it doesn't take malicious intent for this to happen!
Heck, I don't log my food accurately *even when I desperately try to do so* unless I refuse to open my mouth before logging the next morsel--and this includes Costco samples, or trying the food I'm cooking!
And that's OK!
Because even if you're not logging perfectly, as long as you can behave consistently, you can adjust!
And don't do it by trying to cut 800 or 1000 Calories a day... it will backfire unless you have A LOT of weight available to lose.2 -
Talan79. https://tdeecalculator.net/
Basal Metabolic Rate 1,199 calories per day
Sedentary 1,439 calories per day
Light Exercise 1,648 calories per day
Moderate Exercise 1,858 calories per day
Heavy Exercise 2,068 calories per day
Athlete 2,278 calories per day
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Talan79. TDEE website....
Basal Metabolic Rate 1,199 calories per day
Sedentary 1,439 calories per day
Light Exercise 1,648 calories per day
Moderate Exercise 1,858 calories per day
Heavy Exercise 2,068 calories per day
Athlete 2,278 calories per day
You say you never stop moving and you also exercise for 30 minutes a day. That would mean you're not sedentary, at least by how I understand the term.4 -
Talan79. https://tdeecalculator.net/
Basal Metabolic Rate 1,199 calories per day
Sedentary 1,439 calories per day
Light Exercise 1,648 calories per day
Moderate Exercise 1,858 calories per day
Heavy Exercise 2,068 calories per day
Athlete 2,278 calories per day
So given this, I would guess you are between moderate exerciser??, so at 1200 cals you should be losing weight...
Are you weighing all solid foods with a kitchen scale, and measuring all liquids with measuring cups/spoons?
If not, you may be eating 10-50% more than you think you are thereby eliminating your deficit2 -
You are not sendentary if you are moving all day & exercise for 30 minutes.
Are you using a digital food scale?
Like others have mentioned, unless you are weighing all solids, your calorie intake could be higher than you think.1 -
I find my Fitbit very accurate. I have a basic model (Zip) that is essentially a step counter. Heart rate monitors are not as accurate for me because my heart rate increases a lot even for moderate exercise so they tend to overestimate my burn.2
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