Deficit Fitbit has me on VS the deficit I put myself on for 11 months...help me understand!

[ABetterMe-75lbs]

Hello,

So to start I just got my Fitbit Alta HR in the hopes it would help me manage my calories better. Over the past 11 months, I have lost 75lbs by restricting my daily caloric intake to 1200 calories. High fat, minimal carbs, and moderate proteins. I went from 230lbs to 153lbs. Once I got into the 150's I noticed my weight did not change. I got the Fitbit to help with that because I noticed for the past month I have been eating over 1400 calories a day and I saw it as my weight was being maintained.

So the problem is, I am on the -750 deficit on my Fitbit. This has me at a calculated calorie budget of over 1400 calories! Today for example, it says I burned over 1800 calories and ate over 1300 calories. This is very frustrating for me because I have been eating 1200 calories a day to lose weight, and most online weight loss calculators say I have to eat under 1200 calories a day to lose at least 1lb a week. So why does Fitbit have my daily calorie intake over what most other calculators say I should be eating to lose weight? Please let me know as I am trying to get down to 140 by June! 

Fitbit has me over a 1400 calorie a day, when my original deficit was 1200!

[Esya]

Seeing you have a HR enabled device, it tends to overestimate your calories burned, especially the Alta HR I would say as can be seen in this post from @Dominique. FitBit is a device that aims to estimate our calories burned, but it will never be exact for everyone as we are all different. If you know that 1200 calories a day works for you, then eat until you see you reached that amount. You can also change the FitBit to a deficit of 1000 so the budget provided by FitBit will be smaller.

[Cottongrass]

This is interesting for me. I have a Charge2. I also think Fitbit is too generous in the calorie allowance. I set mine to -750 and only lose weight if I actually eat more like -1000. When I started, I did what it recommended and stayed the same which was discouraging to say the least...

No solution--just saying I have a similar experience!!

[EmjayH]

I have a charge 2 and generally subtract 15% off my daily calorie burn. Doing this makes it close to equal the calorie burn on my fitness pal. I assume this to be rather close to my actual stats. Seems to be working so far 

[ThatGreen]

Forum seems to have eaten my original post, so I'll try again:

Congrats on your loss so far!

I had a look at your profile to get more stats and from what I deduced, your basic metabolic rate (BMR) is ~1450. This is the calories your body uses to function and people will often say this should be your minimum intake. We'll look away from that recommendation for this breakdown, but it's a thing to keep in mind.

If your activity level is sedentary, you'll burn ~1750 calories per day, which seems to match your screenshot.

This means that for you to truly be on a 750 calorie deficit plan, your intake should be around 1000 calories per day, which isn't generally recommended.

I would suggest that you adjust your plan to a 500 cal deficit, which would give you 1250 cal to eat every day and result in a theoretical 1lb loss per week.

OR

Stay on your 750 cal plan and aim to burn around 2000 a day, which would still give you around 1250 cal to eat every day.

The math will always be burned cal - food cal = deficit. One pound is roughly 3500 cal.

Not to crush your goals, but for you to lose 13 lbs before june, you would have to lose ~4,3 lbs a week, which is unreasonable and would be equal to a 15000 calorie deficit every week, or 2150 cal per day, which is already more than you burn.

However, if you stick to a 750 deficit plan, you can expect to reach 140 in roughly two months.

Good luck no matter what you go for!

Disclaimer: All of this is theoretical and just the basic math. Your body might respond differently because a million and one reasons and calories in/out are not always correct.

Also my math might be wrong because I'm in a hurry.

[ThatGreen]

Forum seems to eat/not post this, so I'll try yet again:

Congrats on your loss so far!

I had a look at your profile to get more stats and from what I deduced, your basic metabolic rate (BMR) is ~1450. This is the calories your body uses to function and people will often say this should be your minimum intake. We'll look away from that recommendation for this breakdown, but it's a thing to keep in mind.

If your activity level is sedentary, you'll burn ~1750 calories per day, which seems to match your screenshot.

This means that for you to truly be on a 750 calorie deficit plan, your intake should be around 1000 calories per day, which isn't generally recommended.

I would suggest that you adjust your plan to a 500 cal deficit, which would give you 1250 cal to eat every day and result in a theoretical 1lb loss per week.

OR

Stay on your 750 cal plan and aim to burn around 2000 a day, which would still give you around 1250 cal to eat every day.

The math will always be burned cal - food cal = deficit. One pound is roughly 3500 cal.

Not to crush your goals, but for you to lose 13 lbs before june, you would have to lose ~4,3 lbs a week, which is unreasonable and would be equal to a 15000 calorie deficit every week, or 2150 cal per day, which is already more than you burn.

However, if you stick to a 750 deficit plan, you can expect to reach 140 in roughly two months.

Good luck no matter what you go for!

Disclaimer: All of this is theoretical and just the basic math. Your body might respond differently because a million and one reasons and calories in/out are not always correct.

Also my math might be wrong because I'm in a hurry.

[DavidSchneier]

I subtract 600 from what my Charge 2 estimates my calories burned to be, then apply an additional adjustment equal to 10% of the calories I recorded as having consumed. The 600 is because I have hypothyroidism and definitely don't metabolize my food the way an average person does, and the 10% is because us humans are sucky at accurately recording every single thing we eat, even when being insanely vigilant. I track the numbers in a spreadsheet and can typically forecast within a 1/2 pound what my weight will be on a given day based on these adjustments.

But once you have it all mapped out, watch the magic happen.