Does Fitbit way overestimate calories burned?

JennyL791

I just got a Fitbit last week, synced it, and suddenly my "calories burned" tally is so much higher. Even on days where I do no exercise of any kind. I weighed myself this morning, 5 days after I got it, and there has been no change. Should I be ignoring what Fitbit says, either on days when I don't actually exercise, or even on all days? Meaning, should I not be eating those calories back? I'm suddenly reading that this whole "starvation mode" thing is a myth, this is news to me. Some days I can easily have close to 1,000 calories left when I go to bed. Can that be right? Perhaps there's a way to change a setting of some sort somewhere? I'm new to Fitbit and to MyFitness Pal, so please assume no knowledge on my part.

Thank you!

shadowfax_c11

Nope. You should not ignore what Fitbit is telling you. How many steps are you averaging in a day? I know I can easily gain up to 1,000 extra exercise calories in a day from just all of the walking I do. More than likely the activity level you selected on MFP was not correct for your actual energy use.

malibu927

Five days isn't enough of a time frame to know whether it's working for you or not. But it shouldn't be massively high, especially if you have a Zip/One. What kind of adjustment is it giving you on non-workout days and how many steps do you get?

yarwell

Seems OK for me, a lazy day gets me no extra cals and 5000 steps plus brings me more allowance.

azulvioleta6

You know that it includes your BMR, right?

Lourdesong

On your fitbit profile (not the dashboard) it will show 30 day average intake vs. burn average. If you eat back your fitbit adjustments to MFP for 30 days, then compare your loss to what fitbit burn/intake expected you to lose, you can adjust from there.

Some people find fitbit overestimates their burn once they have enough data, but it seems to be just as common that people find that Fitbit underestimates their burn.

The only way to know what is the case for you is to get enough data following fitbit and compare to your actual results. 5 days isn't enough.

JennyL791

So, I probably fall somewhere between sedentary and lightly active. Or maybe I think I'm sedentary but I'm lightly active. I have it set to sedentary because I don't think what I need is MORE calorie allowance.

Yesterday was basically a couch potato day, and it said I burned 148 cals in exercise. I did walk the dog for 12 minutes, but it wasn't remotely strenuous.

On a day when I had a strenuous workout, it said I burned 528 exercise cals.

Other days, where I was basically at home not doing much but not sitting around the whole day either, it says 3-400 exercise cals. These are the days that feel off to me.

Is it really true that if I go to bed with 600 calories uneaten, and I'm not feeling deprived, I'm full and satisfied, that I won't go into "starvation mode?" Is it okay to let those 600 calories go uneaten? This week I was so surprised at these metrics but I figured out a way to eat the calories back. I know 5 days isn't really enough time, but I also know my body and I should have lost, even if just a half pound, so I'm thinking it's that I ate back calories I shouldn't have eaten back. I'm wondering if maybe Fitbit is mistaken in my stride length or activity level, or something is just off.

I mean, it's not like these calories just started ACTUALLY being burned when I got the Fitbit. Nothing physical has changed.

malibu927

Starvation mode is a myth. However, a higher calorie deficit can lead to muscle loss, hair loss, weakened organs, exhaustion, irregular/no periods, so it's best to eat them back. Most people have success eating them all, some can only eat half. It's also important to remember that weight loss isn't linear, and there are several factors that play into how much you weigh at a given time.

JennyL791

"It's also important to remember that weight loss isn't linear, and there are several factors that play into how much you weigh at a given time."

Yes, this is so frustrating. I am always battling a thyroid issue, plus I still nurse my daughter, but only a little. I am not taking those calories into account because I honestly don't think she's getting that much anymore. I'm just trying to avoid feeling discouraged, so I'm probably trying to solve the problem before I know for sure it's a problem.

earlnabby

My Fitbit gives me a TDEE that is really close to the one I calculated from my actual numbers. It can be very accurate, but the more you wear it, the more accurate it will become because it will have much more data to work with.

When you first get it, it will calculate according to averages for your height, weight, and how fast you move. Over time it will also have actual calories eaten, weight lost, etc. to factor in, so it can more accurately figure the burn based on real life numbers. To start, maybe eat back about 50-75% of the calories it gives you and see how things work out. If you are losing faster than your plan, eat back more.

JennyL791

Out of curiosity, what is the problem with losing faster than your plan, especially if you choose your plan somewhat arbitrarily?

Sued0nim

Mine is accurate

Have you set it up properly?

You know it's giving you TDEE and not exercise burn

Judge it against weight loss over 6-8 weeks to check

earlnabby

JennyL791 wrote: »

Out of curiosity, what is the problem with losing faster than your plan, especially if you choose your plan somewhat arbitrarily?

Depending on how aggressive your plan is, you might be losing lean body mass as well as fat. Depends on where you start. I didn't have to worry because my plan was to lose 1 lb. a week, even though I had over 100 lb to lose and had enough body fat so could lose up to 2 lb a week safely. Others may not have that much.

malibu927

A thyroid issue, depending on well you have it under control, can mean you aren't burning as much as you think. I'll wait for @editorgrrl to chime in, as she's an expert in both thyroid issues and Fitbit knowledge.

NancyN795

There have been many times when I "should" have lost and haven't and many times when I "shouldn't" have lost and have. Everyone is right - 5 days is not enough to judge, even if you've been logging your food carefully.

I second the recommendation to join the Fitbit Users Group and read the FAQ there:

http://community.myfitnesspal.com/en/discussion/10098937/faq-syncing-logging-food-exercise-calorie-adjustments-activity-levels-accuracy/p1

I've learned a lot from that group. Not just about how my Fitbit interacts with MFP, but about making sure that I do this weight loss/fitness thing the right way. (Such as, why - even though starvation mode is a myth - it isn't good to have too big a deficit and why exercise is essential to keeping your metabolism going.)

I find logging my food accurately is the hardest part. I get sick of weighing everything, but I know it is necessary for me. I think my Fitbit gives me close to the right adjustment but maybe not exactly correct. The last time I felt like I'd been logging my food well enough to compare, it seemed to be overestimating by about 80 calories a day (or maybe my logging was off by that much). So, I've started adding 100 "Quick Add Calories" to my MFP diary every morning, to offset it. I'm again trying to log accurately enough and I'll see in a few weeks if my offset is good.

Also, with an activity tracker such as a Fitbit estimating your calories burned, getting your activity level set just right in MFP isn't nearly as important - as long as you have negative calorie adjustments enabled. I keep my activity level set to Sedentary, even though I tend to get a 600+ calorie adjustment, even on a relatively inactive day.

editorgrrl

I have Hashimoto's (autoimmune thyroid disease), and I lost just like everybody else—by eating fewer calories than I burn. And I've maintained for a year. I did three things:

1. Follow the advice in the Sexypants post: https://community.myfitnesspal.com/en/discussion/1080242/a-guide-to-get-you-started-on-your-path-to-sexypants/p1

2. Trust my Fitbit.

3. Be patient!

You can learn more in the Fitbit Users group: http://community.myfitnesspal.com/en/group/1290-fitbit-users

editorgrrl

JennyL791 wrote: »

I'm new to Fitbit and to MyFitness Pal, so please assume no knowledge on my part.

Your Fitbit burn is TDEE, the number of calories necessary to maintain your current weight.

Connect your accounts at http://www.myfitnesspal.com/fitbit

Enable negative calorie adjustments: http://www.myfitnesspal.com/account/diary_settings

Set your goal to .5 lb. for every 25 lbs. you're overweight: http://www.myfitnesspal.com/account/change_goals_guided

Ignore your Fitbit calorie goal & follow MFP's, eating back your adjustments.

NancyN795

JennyL791 wrote: »

Out of curiosity, what is the problem with losing faster than your plan, especially if you choose your plan somewhat arbitrarily?

Not a problem if you chose a plan that wasn't too aggressive. My goal is set to 0.5 pound per week, even though I could safely lose 1.5 pounds per week (based on how overweight I am). So, I try to generally have between 0 and 500 calories left at the end of the day and - when I'm logging accurately - I generally lose an average of 1 pound per week.

However, if you "arbitrarily" chose to try to lose 2 pounds per week and you've only got 10 pounds to lose, then that's a problem. You can't really lose fat that fast. That rate of loss is for people who need to lose more like 100 pounds.

Bottom line - you shouldn't chose your plan arbitrarily.

JennyL791

I didn't have negative calorie adjustments enabled. I've done that, but can someone explain what that is? It's probably really obvious but this is the first time I've done weight loss without someone just telling me how many "points" to eat, so all of this is new to me.!