what is the daily calorie deficit?

[victoriagb]

Im confused abut the dialy calorie deficit.  I exercise alot so my dialy calorie intake amount increases.  I still always have a large daily calorie deficit.  Doe this mean I  should eat more calories up to the deficit.   

[Malpeg · Accepted solution]

Calorie deficit is calories burned minus calories eaten. Whether you should eat up to that amount depends on whether you're trying to lose weight. My goal is to have a deficit of 500-750 calories per day.

[Colinm39]

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@victoriagb wrote:

Im confused abut the dialy calorie deficit.  I exercise alot so my dialy calorie intake amount increases.  I still always have a large daily calorie deficit.  Doe this mean I  should eat more calories up to the deficit.   

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@victoriagb

The calorie deficit is your goal and -500 calories/day or -3500 per week = one pound. Fitbit will always ensure your are healthy and if you have very active days the calculations will include extra nourishment calories but will always keep the deficit as you have set it in your food plan. Don't fall for the trap of eating the extra, it is up to you and what your body is "telling" you.

[Heybales]

So the brunt of this, since this is new to you.

If you selected a weight loss goal - your eating goal ALREADY has a deficit from your daily burn.

Don't think bigger is better by making even more deficit.

The Fitbit already underestimates your daily burn, auto deficit there too.

If bigger deficit was better - why don't people just stop eating and lose all the weight fast?

Because the weight would be much more than just fat.

[SunsetRunner]

You don't want to go to much into a deficit because that's how your body gets into fat storing mode. The human body is an extremely adaptive mechanism and it tries everything possible to preserve itself. So if it notices that it's not getting enough food for energy it will hold on to as much energy as possible - and the best way for it to hold energy is as fat. You want to be in a deficit but you also want to make sure you feed your body and prevent insulin fluctuation but most importantly - LISTEN to your body and know when you don't need another bite. 🙂

[MonicaLBP]

Thank you. My question has been "-500 from what? From a 2000 calorie diet, a 1500 calorie diet?" Never even crossed my mind that it's 500 fewer calories than I burn in a day. Thank you again 🤗

[Glenda]

Why do you say Fitbit always underestimates the calorie burn.  I believe you, but how do you know?  My fitbit said I burned 1174 calories Tuesday.  How many should I eat to lose weight?   ( Probably not 674.)

[Heybales]

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@Glenda wrote:

Why do you say Fitbit always underestimates the calorie burn.  I believe you, but how do you know?  My fitbit said I burned 1174 calories Tuesday.  How many should I eat to lose weight?   ( Probably not 674.)

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There are 4 components to a person's daily burn - TDEE - Total Daily Energy Expenditure

BMR - Basal Metabolic Rate - Fitbit uses a formula similar to Mifflin- St Jeor that vast majority of people are within 5% of (unless in an extreme diet or with a disease). Also called REE - Resting Energy Expenditure.

NEAT - Non-Exercise Activity Thermogenesis - daily activity basically, with Fitbit and others, steps calculates to a distance, distance and time and weight give a very accurate estimate of calories burned (for level walking).

EAT - Exercise Activity Thermogenesis - Fitbit and others slip into HR-based calorie burn to estimate this - sometimes that's a bad idea as step-based would be more accurate, inflated on anything that is not steady-state aerobic exercise.

TEF - Thermic Effect of Food - it takes calories to process and metabolize food, averages about 10% of the calories eaten. Not taken into account by most trackers, including Fitbit. Move to higher protein and it can move on up to 20%, move to higher fat and it goes lower. If eating a lot it can be decently high number from the TDEE.

That's what I mean by some under estimating.

Then again it's usually inflated on much of the lighter exercise done, and most people log food underestimating how much they actually ate - so I'm betting most trackers call that missing component a good buffer.

500 cal deficit isn't reasonable for you.

Another way to look at it from studies, with a decent amount of fat to be lost (somewhere around 40-50 lbs), 1% of your body weight weekly isn't bad.

Less than that 0.75% is safer to preserve muscle mass. If down to final few either keep it there but briefly, or use 0.5%

If you weighed 110 lbs and 100 was reasonable goal weight, that would be 0.55 lb a week, or 3500 cal/lb of fat x 0.825 = 1925 weekly deficit, or 275 daily deficit.

Since accuracy on logging food (labels are allowed to be upwards of 20% inaccurate) becomes hard at that small numbers, and not eating much anyway, alternate approaches may work better.

Like alternate week diet, week on, week off.

Or become more active so you have a bigger range. 275 off sedentary daily burn compared to being very active daily. one is probably more reasonable.

Just make sure you don't become more inactive at other times to compensate for that - then again the Fitbit will kinda help see that happening.

[MonicaLBP]

I took a metabolic rate test at my weight loss clinic a couple weeks ago and it said I was burning about the same number of calories a day as my Fitbit was saying. But I'm with you on not trusting the info from my Fitbit. Plenty of the other readings have been completely inaccurate. 

[Heybales]

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@MonicaLBP wrote:

I took a metabolic rate test at my weight loss clinic a couple weeks ago and it said I was burning about the same number of calories a day as my Fitbit was saying. But I'm with you on not trusting the info from my Fitbit. Plenty of the other readings have been completely inaccurate. 

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All that test was measuring was BMR, actually RMR - Resting MR since you were probably not sleeping but awake and resting.

RMR is just a tad higher than BMR. That is a very accurate test.

As long as you haven't been in a diet anyway. Diets can suppress your BMR/RMR if extreme - and sadly over 50% of dieters attempt extreme.

If you mean your RMR reading was about the same calories as Fitbit shows for an entire day of being awake and actually moving - then indeed the Fitbit is WAYYYYYY off, since the mere act of getting up and moving should burn way more than RMR.

If you mean your printout from the test took that RMR and estimated, again estimated, a daily burn (TDEE) - that is total formula at that point.

Hopefully they asked you some questions about your average daily activity to select from the likely 4-5 basic levels they always seem to select from.

Most are using a multiplier based on a Harris study from 1919. Yes, over a 100 years old and very outdate with better formulas since then.

At least based on a better foundation maybe.

But your Fitbit is still on you and seeing your actual activity levels day by day, your or the tech's guess from 4-5 levels of activity - eh - may have lucked out, may not have.