Same goal on MFP and Fitbit but calories are way off

JuliaDastous24
JuliaDastous24 Posts: 1 Member
edited November 2024 in Health and Weight Loss
Hi!

I have the same goal of 1.5lbs per week set for Fitbit and mfp. I have mfp set to not very active so that I can see the calories given to me each day from exercise/Fitbit.

I'm very confused however because the calories I have left are at least 200 calories off between the 2 tools always. I know Fitbit gives a deficit of 750 calories per day to reach my goal, but I can't seem to find what the MFP deficits. I feel like that can be the only reason why they are so different.

Thanks!
Julia

Replies

  • sbrandt37
    sbrandt37 Posts: 403 Member
    It's hard to know without knowing all of the data you put into each one (along with how the do their calculations), but both would give you a deficit of 750/day for a 1.5 pounds/week weight loss goal. The Fitbit presumably has better information about your actual activity level throughout the day, but both are just estimates anyway. Your level of weight loss over time will tell you what your body really needs relative to what they are telling you.
  • size102b
    size102b Posts: 1,370 Member
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories
  • Tacklewasher
    Tacklewasher Posts: 7,122 Member
    I know that the calculations for my Garmin (on Garmin connect) are different than the MFP calculations. Maybe 100 or so different. I just stick to the MFP numbers.

    The deficit is the same (750 cals for 1.5 lbs) but they use different formulas to calculate the base number (NEAT) and don't quite agree.

    Pick one (I suggest MFP) and stick to it until you see how your weight loss is going (so at least 4 weeks). These things are all estimates anyway.
  • kshama2001
    kshama2001 Posts: 28,055 Member
    Hi Julia,

    MFP also gives you a daily deficit of 750 calories in order to lose 1.5 pounds per week. It may not spell this out anywhere.

    Check the calories in both locations as close to midnight as possible and see if they are aligned then. If so, the difference earlier in the day is due to MFP assuming you will live until midnight and FitBit insisting on you actually burning your BMR calories before issuing them.
  • shadow2soul
    shadow2soul Posts: 7,692 Member
    Let me guess, MFP says you have 200 more calories than fitbit does.

    If this is the case it's because MFP has a minimum intake level that it will not dip below. Fitbit has no such minimum.

    For example (using rough estimates of my own numbers):

    I set MFP to the lowest setting. MFP says based on my stats and activity level setting I should burn roughly 1600 calories a day without exercise.

    What does that mean for my weight loss calorie goal? The max deficit MFP will let me have is 400 calories. I could tell it I want to lose 2 lbs a week, but the system will still bottom out at a goal of 1200 with a max deficit of 400 calories.
  • tinkerbellang83
    tinkerbellang83 Posts: 9,158 Member
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    You can just turn negative adjustment on, you don't need to set it to sedentary. I have mine set to lightly active and eat all my calories back.
  • rileysowner
    rileysowner Posts: 8,354 Member
    shadow2soul wrote: »
    Let me guess, MFP says you have 200 more calories than fitbit does.

    If this is the case it's because MFP has a minimum intake level that it will not dip below. Fitbit has no such minimum.

    For example (using rough estimates of my own numbers):

    I set MFP to the lowest setting. MFP says based on my stats and activity level setting I should burn roughly 1600 calories a day without exercise.

    What does that mean for my weight loss calorie goal? The max deficit MFP will let me have is 400 calories. I could tell it I want to lose 2 lbs a week, but the system will still bottom out at a goal of 1200 with a max deficit of 400 calories.

    Generally if a woman gets 1200 calories as her goal she is setting to aggressive a weekly weight loss goal. If you are obese 2 pounds a week is an appropriate goal. However, if you avatar picture is yours, then 2 pounds a week is far too aggressive. If you only have 20 pounds or less to lose, half a pound a week is pretty much the max you should shoot for. Maybe three quarter of a pound a week for the first 5 pounds.
  • size102b
    size102b Posts: 1,370 Member
    tinkerbellang83 wrote: »
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    You can just turn negative adjustment on, you don't need to set it to sedentary. I have mine set to lightly active and eat all my calories back.

    You do know exercise calories are over estimated on all devices
  • WinoGelato
    WinoGelato Posts: 13,454 Member
    OP try not to look at calories in FitBit. They are never going to match. They use different algorithms. It used to drive me batty trying to figure out why they were different.

    Set the same goal in both.
    Make sure your goal is reasonable (you said lose 1.5 lb/week, do you have more than 50 lbs to lose?)
    Set an appropriate activity level. If you average 8k or more steps per day, you may want to think about choosing lightly active not sedentary.
    Enable negative calorie adjustments (this is a good safety net for days you are less active than normal: illness, road trips, etc so that you don't overeat.
    Log all calories in MFP, as accurately as possible
    Log any non step based activity in one or the other system, but not both.
    Look only at MFP for calories remaining
    Cautiously Trust the adjustments, if they seem quite large, you may want to start with only eating back a percentage of the calories; and you may consider upping your activity level setting in MFP.
    Give the systems a couple of weeks to figure out your patterns, they will get more accurate over time.
    Monitor and adjust based on your actual rate of loss.

    Good luck!
  • shadow2soul
    shadow2soul Posts: 7,692 Member
    edited March 2017
    rileysowner wrote: »
    shadow2soul wrote: »
    Let me guess, MFP says you have 200 more calories than fitbit does.

    If this is the case it's because MFP has a minimum intake level that it will not dip below. Fitbit has no such minimum.

    For example (using rough estimates of my own numbers):

    I set MFP to the lowest setting. MFP says based on my stats and activity level setting I should burn roughly 1600 calories a day without exercise.

    What does that mean for my weight loss calorie goal? The max deficit MFP will let me have is 400 calories. I could tell it I want to lose 2 lbs a week, but the system will still bottom out at a goal of 1200 with a max deficit of 400 calories.

    Generally if a woman gets 1200 calories as her goal she is setting to aggressive a weekly weight loss goal. If you are obese 2 pounds a week is an appropriate goal. However, if you avatar picture is yours, then 2 pounds a week is far too aggressive. If you only have 20 pounds or less to lose, half a pound a week is pretty much the max you should shoot for. Maybe three quarter of a pound a week for the first 5 pounds.

    I was just using me as an example since it's often the difference between the 2 programs. I have a manually calculated goal of 1880 (though to be honest I am currently eating more). I can't even imagine trying to maintain a 1000 calorie a day deficit at my weight.

    Edit: And yes that is me in the pic. I took the pictures last week.
  • rileysowner
    rileysowner Posts: 8,354 Member
    WinoGelato wrote: »
    size102b wrote: »
    tinkerbellang83 wrote: »
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    You can just turn negative adjustment on, you don't need to set it to sedentary. I have mine set to lightly active and eat all my calories back.

    You do know exercise calories are over estimated on all devices

    You do know blanket statements and generalizations are rarely helpful...

    I have had a FitBit for 3.5 years. I have my MFP activity level set at active because I average 14K steps/day. I eat back all my exercise calories from FitBit. I lost the weight I set out to lose, in the time that I wanted to lose it, and am now maintaining by trusting the FitBit adjustments.

    Also for the record I'm a petite female with a TDEE of 2200, so yeah, eating back that many cals could be a risk but since I've been in maintenance for 2.5 years, I trust my device.

    I was going to say much the same except I don't have a Fitbit.
  • tinkerbellang83
    tinkerbellang83 Posts: 9,158 Member
    size102b wrote: »
    tinkerbellang83 wrote: »
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    You can just turn negative adjustment on, you don't need to set it to sedentary. I have mine set to lightly active and eat all my calories back.

    You do know exercise calories are over estimated on all devices

    And yet I am losing at my expected weight loss rate, go figure! Whilst all devices can be inaccurate they aren't all wildly so, the 50% guidance is just a starting point and should be reviewed after a couple of weeks with the weight loss rate being method of determining it's accuracy. Setting it to sedentary if you're not sedentary isn't going to make it any more accurate.
  • Sassafras106
    Sassafras106 Posts: 73 Member
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    Not necessarily...
    I have mine synced and eat most of my exercise calories ( only leaving 2-300, out of over a thousand exercise calories some days) and I'm set to active. I lost 2 lbs per week until I changed my goal to 1.5
  • SusanMFindlay
    SusanMFindlay Posts: 1,804 Member
    size102b wrote: »
    tinkerbellang83 wrote: »
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    You can just turn negative adjustment on, you don't need to set it to sedentary. I have mine set to lightly active and eat all my calories back.

    You do know exercise calories are over estimated on all devices

    Then why do I lose weight exactly as predicted when comparing my intake to my FitBit burn?

    If I followed your advice ("choose sedentary and only eat half the exercise calories"), I'd be undereating by 600 calories every day!!!

    Personal activity trackers are not the same as gym machines (notorious for overestimating) or MFP's exercise database (not quite as bad, but still overestimates). They're not perfect for everyone - because not everyone has exactly the average BMR that the trackers use in their calculations. But they're usually only off by 100-200 calories at most. IN EITHER DIRECTION. And that's easy to figure out by comparing observed weight loss to predicted weight loss. Once a person works out their personal correction factor (if they need one), they apply it and continue with the plan.
  • MaybeLed
    MaybeLed Posts: 250 Member
    I have had a similar experience to others

    It's a bit trial and error, you just have to work out what works for you. Eat as MFP suggests for 6 weeks or so eating your fitbit adjustment and see how much you lose in that time, is it more or less than predicted? Use a trendweight app/website to see your losses. MFP is designed so you eat back your exercise calories. When I first started I made it too complicated for myself, I was only eating back 75%, setting myself as sedentary, giving myself too few calories at the start of the day. Got sad and hungry ate too much. Even though I have a desk job, I walk a lot to and from work, so I'm not sedentary.

    I’ve set myself as lightly active (regularly do between 8-12k steps 5-7 days a week) eat those calories including 100% of activity, I’ve enabled negative adjustments for the days I don’t get off the sofa and I’ve been regularly losing 20% more than anticipated, which is a reasonable error combining both human and technical.

    For example to lose 1lb a week I should eat 2000kcal a day (net). Calculating a 28 day period (before my diet break) I’ve eaten 2053 kcal a day (net) and in that time I was anticipated to lose 4lb but I’ve lost 4.9lb (according to www.trendweight.com).

    TL:DR The thing is to trust the numbers, give it a go for a reasonable period. If it’s not working for you, you may need to play with the numbers.
  • RosieRose7673
    RosieRose7673 Posts: 438 Member
    size102b wrote: »
    tinkerbellang83 wrote: »
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    You can just turn negative adjustment on, you don't need to set it to sedentary. I have mine set to lightly active and eat all my calories back.

    You do know exercise calories are over estimated on all devices

    These estimates are based off of what the average person would burn. So obviously there's a spectrum of what people burn in a day doing various activities.

    Many people find them spot on. I had an Apple Watch and I found it actually underestimated my calorie burn. I used it to lose weight and ended up just adding a few hundred calories a day for my calorie allotment. When maintaining, i tried to just stay to the amount that Apple Watch said.

    I lost weight despite trying to maintain. I also gave up on the Apple Watch because it drove me nuts to see that I would be in the red despite me still losing weight.

    I now have a FitBit Charge 2- I haven't had it long enough to make an accurate assumption but currently it seems pretty accurate. Only time will tell.

    In all, people must make adjustments if they notice that it seems inaccurate.
  • TimothyFish
    TimothyFish Posts: 4,925 Member
    size102b wrote: »
    tinkerbellang83 wrote: »
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    You can just turn negative adjustment on, you don't need to set it to sedentary. I have mine set to lightly active and eat all my calories back.

    You do know exercise calories are over estimated on all devices

    That's actually not true. Some under estimate. Though Fitbit is one of the ones that overestimates.

    However, the devices tend to be consistent in either overestimating or underestimating. As long as you aren't trying to get a specific calorie count, they work well to tell you if you are burning more or less than you normally do.
  • kshama2001
    kshama2001 Posts: 28,055 Member
    size102b wrote: »
    tinkerbellang83 wrote: »
    size102b wrote: »
    If you are eating exercise calories you have to set mfp as sedentary and only eat upto half exercise calories

    You can just turn negative adjustment on, you don't need to set it to sedentary. I have mine set to lightly active and eat all my calories back.

    You do know exercise calories are over estimated on all devices

    Disagree. I can safely eat back 100% of the exercise calories given to me by the FitBit One, which is less generous than the MFP exercise database.
  • kshama2001
    kshama2001 Posts: 28,055 Member
    shadow2soul wrote: »
    Let me guess, MFP says you have 200 more calories than fitbit does.

    If this is the case it's because MFP has a minimum intake level that it will not dip below. Fitbit has no such minimum.

    For example (using rough estimates of my own numbers):

    I set MFP to the lowest setting. MFP says based on my stats and activity level setting I should burn roughly 1600 calories a day without exercise.

    What does that mean for my weight loss calorie goal? The max deficit MFP will let me have is 400 calories. I could tell it I want to lose 2 lbs a week, but the system will still bottom out at a goal of 1200 with a max deficit of 400 calories.

    Good point. I forgot about the MFP minimum. I went for the 2 pounds per week goal when I first joined MFP and didn't make it past lunch.
  • StaciMarie1974
    StaciMarie1974 Posts: 4,138 Member
    If both have the same deficit (1.5 pounds per week for 750 calories per day deficit):

    They will be off during the day because MFP assumes you will maintain your activity level until midnight, while in reality at some point you're going to go to bed. Fitbit assumes bmr for the day not yet happened. For days in the past, already completed they should be pretty close unless:

    a ) You have a manually set calorie goal at MFP, or otherwise they are NOT set to the same weight loss goal

    b ) You have a 1200 starting calorie goal at MFP, which means your intended rate of loss is more aggressive than you can achieve without exercise. Such as if MPF thinks you will burn 1600 per day, and you want to lose 1.5 pounds per week, you'll be assigned 1200 which is actually a 400 deficit. So your goals really are not the same across devices.
    JuliaDastous24 wrote: »
    Hi!

    I have the same goal of 1.5lbs per week set for Fitbit and mfp. I have mfp set to not very active so that I can see the calories given to me each day from exercise/Fitbit.

    I'm very confused however because the calories I have left are at least 200 calories off between the 2 tools always. I know Fitbit gives a deficit of 750 calories per day to reach my goal, but I can't seem to find what the MFP deficits. I feel like that can be the only reason why they are so different.

    Thanks!
    Julia

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