Yes. Mine overestimates by somewhere between 12 and 15%. I maintained for 3 months eating at a 500 cal deficit. I've only got a couple months of data after I dropped another 300-400 cal. I'm losing again, but because of my inconsistencies and normal weight fluctuations, I'm not sure how off it is. It's between 12 and 15% though. Another month or two and I'll have enough of a sample to say for sure.

Mine seems pretty accurate, though perhaps slightly over. I usually lose close to what it says I should, but not always right away, I lose in spurts. So I might be getting a 1000 calorie deficit for a month without losing anything, and then suddenly drop 5 pounds a week for 2 weeks in a row.

I should probably look at long term data and try to get a better picture of it.

Okay, based on my calculations, the reported deficits from my Bodymedia arm band should have resulted in a loss of 43.43 pounds over the last 16 weeks, in reality it has resulted in a 39.9 pound loss. So its pretty close for me, not 100% accurate, but pretty close.

Mine overestimated about 200 Cals a day compared to the Fitbit.

Its too bad everyone is having issues. Mine is accurate well within the parameters that bodymedia said it would be. My TDEE is being overestimated by around 3.5 %, but that results in my deficit being overestimated by about 10%.

I blogged about it here: http://www.myfitnesspal.com/blog/ThriceBlessed/view/week-17-update-592151

I am compensating by adding 10% to my target deficit, deciding to make that adjustment now rather than waiting until I stop losing.

I know that nothing is perfect, MFP also overestimates burn for various activities, heart monitors aren't perfect, and neither are pedometers, so I will stick with bodymedia and simply make adjustments to account for discrepancies.

Also, not everyone's body is the same. Certain hormonal conditions can cause you to lose less. Differences in metabolism can cause the same activity on one person to burn more than another. Medications can cause weight gain/loss. So I figure that no matter what I use, I'll have to make adjustments to suit what is happening with my body vs. what I want to happen with it. So I don't think I'll spend more money on another device right now, I'll just stick with the one I have.

Trying a fitbit flex now to see what it says.

If going to a Fitbit / activity tracker than keep in mind they are two VERY different animals.

I do realize they are different but thank you. I used BM for the last 2 years and prior to a surgery I had used it at least a year before with the same very little results. Although sometimes I wasn't as dedicated as I should have been so thought I was under estimating my calorie intake. I tracked 16 weeks extremely close, according to BM I had a deficit that should have equaled over 26 pounds of loss, in reality I lost 8.6. FitBit Flex is showing almost the same steps but not quite as much vigorous activity (it's hard to get it to show that kind of activity where I didn't have much trouble with BM showing it) and is running 300-400 calories burned a day less than BM. It's worth a shot, at least I don't have to pay a monthly fee and no more issues with the metal making my arm randomly irritated/itchy.

I guess I will have to figure out if my BM is off and recalculate based on that because I LOVE it. Thanks for the info everyone.

You can adjust your height in the profile, and this will bring your burn down. I had to really lower my height (by oveer a foot) in order for it to reflect what was going on in my body. Evidently I have the metabolism of a midget!

There is a post about this in the "In Place of a Roadmap" group.

Okay, I just shrunk an inch, we'll see if that gets my burn down to where it ought to be!

I have been using a Fitbit Zip for the past 5 weeks. By wearing a HRM during workouts and overriding Fitbit's calories for that time period and replacing them with those from the HRM, my estimated calories burned vs. actual weight loss were accurate to within 50 calories per day! That tells me that, while the Fitbit isn't that accurate at measuring exercise activity, it is very effective at measuring my activity throughout the rest of the day. Since buying the Zip, I have added 45 minutes of walking to my daily routine in addition to my workouts to get my step count, and that has really helped my progress.

All that said, I just ordered a BMF, because I have always wanted one and decided it might do a better and more accurate job of helping me lose these last 15 pounds. Every calorie counts in the homestretch! It is also a pain to set up the HRM, record starting time and length of workout in order to override the Fitbit calories, etc. I want to just strap on the BMF and leave it on all day and not have to think about it. I also know I must be burning calories doing dishes and cooking dinner, even though I'm not getting any "steps", and want to be able to quantify that.

My plan is to wear all 3 devices (HRM, Fitbit and BMF) for at least a week or two, maybe even a month, to compare data and try to find the most accurate TDEE, and then stick with just the BMF for the long haul once it has been adjusted. If at some point I stop losing and have trouble in the maintenance phase, I can always go back to the combo to find where the inaccuracies lie.

Okay, just shrunk another 4" to make it a full 5" off height. Seems kinda weird putting my height in a 5'!!

If you are really good about logging your calories you may want to check out "Digifit" it does sync with MFP and Bodymedia and has some trend charts that may help you see what you may want to tweek. If you are a numbers/tracker geek you would probably enjoy it. I like it because I use a HR chest strap to exercise and it is great for seeing detail.

Is this an app or a device?

Remember, even if you log every morsel that goes in your mouth it isn't possible to be 100% accurate on calories consumed. The FDA allows up to 20% (yes 20%) margin of error for noted calories. So if something says it's 500 calories, it could really be 600. Add that up over multiple foods for a given day and that could easily result in a 200+ calories that aren't accounted for in the log. And considering there will be some errors due to portion sizes being off, missed foods, etc. there could be hundreds more calories not accounted for.

I thought maybe my BMF was overestimating my burn, but I always worked on the premise that if I logged 1500 calories I actually at 1500 calories... I never really thought about those extra calories due to the margin of error, etc. I'm starting to think it's more an issue, for me, with calories consumed than my log.

I will say I'm very happy I have my BMF and have found the information it provides very helpful. Recently I started taking some Zumba classes and my BMF would often show my calorie burn around 450 for a 1-hour class and I was working my butt off. I was expecting more, especially since I've seen lots of people with much higher burns, some around 1000 cals, doing Zumba. If I had just assumed around 800-1000 calories burned, or used the ~700 cal burn in MFP I would have been wrong.

I haven't ever compared what I should be losing to what I am losing, but it seems pretty accurate. I think I'll start the spreadsheet, though, just out of curiosity, and because I'm a data nerd.

I have noticed that it is fairly accurate for some types of exercise and not with others....After using it for a couple of months I looked back over my data and noticed that the weeks that I maintained around a 500 to 800-- calorie deficit, I lost around a pound....when I maintained a 1000 - 1300 I lost about 2 lbs. ( I do not know if accurate or not...but I know it is consistent for my body....so I just try to end my day with a constant deficit for the weight loss I want)

Also a lot of the issue with planned activities...I am an elliptical nut and the body media does not get the elliptical right even with the adjustment down closet to the elbow. So for my planned workouts I always take off my Body Media and use my Heart Rate monitor instead...I then go in and manually enter that activity and calories burned...Using these two methods has been great for me and has made the weight loss more consistent.

I had the same issue on my recumbent bike. I ended up moving the BMF to my upper left calf and it seems to log more accurately.