Fitbit confusing me.

My weight is healthy and has been for a long time but my doctor has advised not to lose anymore, MFP gives me 1360 calories to maintain and I was still losing 0.5 pounds per week on that amount.

If we had a family celebration I could maintain, even gain a bit but as soon as I went back to 1360 for a week my weight dropped again and kept dropping.

So I bought a fitbit flex, thought it was the best way to see what I was truly burning and most days it gives me less calories than MFP does.

I am sedentary, female and 105 pounds and at the moment have very few days where I am more active because my health problems have flared up massively.

I don't know what to think now, it feels wrong to defy the fitbit since it is monitoring my activity but if I lose on the 1360 that MFP gives me then eating less is obviously not an option because I will continue to lose weight steadily.

I had heard such good things about fitbit and how accurate they are but it wants me to eat roughly 60 calories less than MFP most days and even MFP calories are too low.

Are fitbits really that accurate or is it just an estimate? Perhaps I should have spent a bit more and got the charge HR, I don't know, just confused really.

Replies

  • bioklutz
    bioklutz Posts: 1,365 Member
    It doesn't matter what fitbit or MFP tells you are still losing weight. Real life data will trump everything else.

    If you are still losing 0.5 pounds a week at 1360 you have a 500 calorie deficit and maintenance calories of 1860. You can try adding all the calories at once or you take a few weeks and slowly add those calories back in.

    You might see a temporary spike in the scale as you add back calories. That is water weight and not fat.
  • kirstenb13
    kirstenb13 Posts: 181 Member
    0.5 lbs a week is a 250 calorie deficit but yes you should definitely eat them.
    It could be that your health issues make your body use a little more energy and that's why the fitbit estimates low, but no matter the reason, increase your food until you don't lose anymore.
  • Christine_72
    Christine_72 Posts: 16,049 Member
    What does fitbit calculate your TDEE as?
  • shadow2soul
    shadow2soul Posts: 7,692 Member
    edited April 2016
    Bella77007 wrote: »
    My weight is healthy and has been for a long time but my doctor has advised not to lose anymore, MFP gives me 1360 calories to maintain and I was still losing 0.5 pounds per week on that amount.

    If we had a family celebration I could maintain, even gain a bit but as soon as I went back to 1360 for a week my weight dropped again and kept dropping.

    So I bought a fitbit flex, thought it was the best way to see what I was truly burning and most days it gives me less calories than MFP does.

    I am sedentary, female and 105 pounds and at the moment have very few days where I am more active because my health problems have flared up massively.

    I don't know what to think now, it feels wrong to defy the fitbit since it is monitoring my activity but if I lose on the 1360 that MFP gives me then eating less is obviously not an option because I will continue to lose weight steadily.

    I had heard such good things about fitbit and how accurate they are but it wants me to eat roughly 60 calories less than MFP most days and even MFP calories are too low.

    Are fitbits really that accurate or is it just an estimate? Perhaps I should have spent a bit more and got the charge HR, I don't know, just confused really.

    just an estimate. The models without HR underestimate for me by about 200 calories per day on average (they don't for everyone, but it looks like your in the same boat as me). Upgrading to a model with a HRM closed that gap for me.
  • bioklutz
    bioklutz Posts: 1,365 Member
    kirstenb13 wrote: »
    0.5 lbs a week is a 250 calorie deficit but yes you should definitely eat them.
    It could be that your health issues make your body use a little more energy and that's why the fitbit estimates low, but no matter the reason, increase your food until you don't lose anymore.

    Yikes! I failed at math today.
  • mk2fit
    mk2fit Posts: 730 Member
    edited April 2016
    Fitbit and MFP can tell you all kinds of stuff. Do what works for YOU! If you need to add some calories to gain or maintain, do it. Are you going to listen to the machines? Keep in mind fitbit is not set up for anything but losing weight. Try IIFYM or Scooby to get your BRM and TDEE and work from there on calories in and out. Best wishes!
  • PAV8888
    PAV8888 Posts: 14,140 Member
    Eat the extra calories.
    Use a trending weight application to record your weight trend. (trenweight.com and weightgrapher.com connect automatically to fitbit.com via integration)

    Give yourself a budget for a SLIGHT weight gain.
    If your doctor is intervening it is unlikely that you're not already below optimum weight and would thus benefit from a slight regain -- slight does NOT mean your former weight: it means a more optimum weight than you're at now!

    Hit that budget on your trending weight app by eating so that you can achieve it (i.e. if you're not gaining towards it... you're not yet eating enough)

    Evaluate how many calories you've been eating/how your trending weight has been responding and adjust based on this information. Make sure that you look at time periods such that a full monthly cycle is included as a lot of water weight changes are associated with TOM.

    Use the fitbit numbers and the above numbers and calculate a % error for your fitbit based on YOU and YOUR logging habits and lifestyle.

    Equipped with that information continue logging happily able to adjust :smile:
  • xmichaelyx
    xmichaelyx Posts: 883 Member
    Don't rely on any device -- Fitbit OR MFP -- to tell you what you should eat. Use either one as a starting point, log your calories religiously, and in a few months you'll know better than anyone how many calories you should be eating.

    Personally, I don't bother logging my activity because that's just one more approximation among many. Calories eaten is a much more exact science than calories burned, and is much more relevant to weight loss/gain.
  • MeiannaLee
    MeiannaLee Posts: 338 Member
    As much as you and I want to believe that online data is 100% accurate, its not :/
    My fitbit caused me to gain weight at the high amount of calories it told me to consume. In the end, it was about 300 calories off.
  • Bella77007
    Bella77007 Posts: 78 Member
    Thank you everyone, I honestly thought having the fitbit would help with maintaining but I was clearly being a bit naive about that, it's a guide, a fun gadget too but if I ate what fitbit told me I burn I would certainly carry on losing.

    Fitbit sets me at 1295 to maintain, most days it says I have burned around 1300 and of course if I eat 1360 and lose then obviously a lower figure wont be enough for me to maintain on.

    My doctor says a healthy BMI is really no lower than 20, I am at 19.5 so gaining a few pounds is no issue although I know plenty of people with a BMI below 20 who are healthy and always thought 18.5 was the lowest however I appreciate that we all vary and she is advising me based on seeing me and having a personal knowledge of me as an individual.

    I will increase calories and see where it takes me, I really thought I was maintaining rather well at one point but we had a few family birthdays so I ate more those days and obviously my weight went up and down a pound or so either way at that time, now to me that looked like normal fluctuations that we see when we maintain but once those celebrations were over I saw the downward trend return and I do need to halt it now.

    Thanks again :)
  • LivingtheLeanDream
    LivingtheLeanDream Posts: 13,342 Member
    Both the app and tracker estimate numbers....if you know yours already by your own tracking of cals over a period of time then you know how much you can eat to maintain.
  • Cbefitforlife
    Cbefitforlife Posts: 83 Member
    I think MFP's calorie count is just a estimate of what you should eat. Everybody's body burns calories differently. Just tweak your calories a little each week until you get to exactly where you want to be. As long as you stay within 2 to 3 lbs. of your goal weight weekly. That is normal to fluctuate that much.
  • lorrpb
    lorrpb Posts: 11,463 Member
    Even HRM is an estimate and it applies only when doing "steady state cardio" not 24/7.
  • jeepinshawn
    jeepinshawn Posts: 642 Member
    mk2loser wrote: »
    Fitbit and MFP can tell you all kinds of stuff. Do what works for YOU! If you need to add some calories to gain or maintain, do it. Are you going to listen to the machines? Keep in mind fitbit is not set up for anything but losing weight. Try IIFYM or Scooby to get your BRM and TDEE and work from there on calories in and out. Best wishes!

    Actually fitbit calculates a daily TDEE so no it should be more accurate, on a daily basis, than either of those two programs.

    To the OP-

    What are your step counts like daily? How accurate is your logging of food, are you weighing things on a scale? I would suggest changing your activity level from sedentary to lightly active. Sounds like if you are sedentary that you are one of the outliers who's metabolism is higher than the average persons. For the average person fitbit and mFP work, for some they need to tweek the program a bit, sounds like you know how many calories you need to maintain, adjusting your activity level to match that calorie count should simplify logging for you..
  • Bella77007
    Bella77007 Posts: 78 Member
    Thanks again, well when I first got the fitbit my daily steps were very low, about 2500 most days which matched with the sedentary activity level and at that point I was still losing 0.5 pounds on 1360.

    My logging is very accurate, I weigh and measure everything at home, the only times I don't weigh or measure are when I have a drink in a coffee shop so I have to use their nutritional guide and that is usually once a week, twice at most.

    We don't eat out often, once a month perhaps and again I have to use guides from the menu since I can't use the food scale.

    Last week I upped my steps a bit due to the fitbit motivation and averaged at 4500 per day which is still sedentary yet I lost 0.8 pounds by the end of the week, it was quite odd seeing as the most calories I burned in any single day according to fitbit was 1635 and the least was 1295.

    I have added 100 extra calories per day for now and will see how it goes for a couple of weeks then adjust accordingly, I do have anxiety so perhaps that kicks my metabolism a bit but I always thought that was a bit of a myth, after all I have had it for years and was obese at one point.

    For the past few days I have managed 7000-10,000 steps per day and would like to keep that up health permitting so may well need to increase further if I do keep it going.

    I will see what happens with the slight increase and tweak it as required :)