Are you losing weight by adhering to the calories in/calories out?

[bunkmungo]

I just got a fitbit flex, and I did so for the purpose of getting healthier and trying to shed a few pounds I picked up working a desk job. I was wondering, becasue I have been trying to stay within the calorie goal- and the more steps I take, the more calories I have left for the day (which makes sense) but I am scared that it is overcounting the calories burned, which would make my diet offset the work I am doing in trying to get more steps in... I am really wanting it to work, and just by trying to meet (and succeeding) the 10,000 steps, I have doubled the steps I normally take a day. I wore it the first day and only took like 4,600 to see how many I had been taking. I just feel like my calorie intake is crazy. I am looking to achieve 1 lb of weight loss a week, for my stature it recommends a 500 calorie deficit, and today I have eaten 1,500 +/- and I still have 250+ left!!

I don't want to ruin my hard work, but I am so hungry and want to take advantage of every last little calorie I can get away with while still losing weight!

[Dominique · Accepted solution]

Yes, calories in calories out is definitely valid. In fact, everything else is secondary (if you want to lose weight/fat). The thing is, there is a margin of error in estimating both calories burned and your intake. If you (or rather your Fitbit) overestimate calories burned by 250 calories and you underestimate your intake by 250 calories, a 500 deficit suddently turns into no deficit at all.

I have been wearing a Fitbit Surge on my left arm and a Fitbit Blaze on my right arm for the past seven days. Here is what they have reported for calories burned:

         Surge vs. Blaze

Day1: 3175 vs. 3062

Day2: 2163 vs. 2091

Day3: 2844 vs. 2676

Day4: 2844 vs. 2659

Day5: 3204 vs. 3287

Day6: 3078 vs. 2737

Day7: 2569 vs. 2549

---------------------------

Average: 2840 vs. 2723

Close enough, but still a discrepancy of 117 calories on a daily basis. If I had been using a Flex, I may have had yet slightly different numbers.

There’s a great article by Precision Nutrition that explains why calories in calories out may seem not to work. Here is an excerpt:

This relationship between ‘energy in’ and ‘energy out’ is called the Energy Balance Equation, and it’s the most commonly accepted model for calculating a person’s energy balance and how much weight they’ll lose or gain over time.
[...]
Understandably, people get really frustrated and confused with the Energy Balance Equation when the numbers don’t seem to add up, or their results don’t match their expectations.

[...]
And it’s a fair frustration. Most of the time, the numbers don’t add up.

The article then gives a number of reasons why the numbers don’t add up. I really recommend reading it.

[Paradise555]

What really helps me for counting calories better is go to myfitnesspal and that website counts the calories in more of a better way. As far as the fitbit side of things unless if you have one with a heartrate moniter (I don't know what one it is) the calories are a estimate.

[Dominique]

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@Paradise555 wrote:

As far as the fitbit side of things unless if you have one with a heartrate moniter (I don't know what one it is) the calories are a estimate.

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Actually, even if your Fitbit has HR monitoring capabilities (Charge HR, Surge, Blaze), calories burned are still an estimate. You can see that from my previous post under this topic, in which I compare calories burned reported by the Surge and the Blaze (worn simultaneously during an entire week). You just have to accept determining calories burned with a Fitness tracker is not an exact science. You would have to be living in a metabolic lab in order to have "accurate" numbers.

[RahnFit]

Eat!!!  If you don't have enough food, you will not lose weight.  The more you walk or burn the more you can eat.  That doesn't mean you overeat.  It means you stay within the green zone.  You should not feel hungry.  If you're hungry you won't continue on your weight loss journey.  Keep getting your steps in and eat right and the weight will come off.  Just wanted to add my 2 cents.  Hope it helps you.

[bcalvanese]

The calories are close enough to ballpark IMO, and it's probably a good idea to leave a calori buffer just in case. In other words make sure you have a few hundred left over.

I power walk every day so I allways have 500 to 1,000 left over every day.

I would say the ones with the HRM are a little more accurate because calories burned is related to heart rate. you just need to stay in the ballpark and realize that it's not exact.

[SebringDon]

You can fine-tune your weight loss program over time as well. Set your goal at a comfortable calorie deficit and watch what really happens for a period of time if you're honest about logging your food intake. If you're losing faster or slower than you should be based on your goal, adjust your calorie deficit accordingly until you're getting the results you expect.

Oh, and by a "period of time" I'm not talking days, but weeks. For myself, about once a month I reevaluate how I'm doing, and so far Fitbit and my metabolism have matched up pretty well. I'm on the 1-pound, 500-calorie-a-day plan, I often leave a couple hundred extra calories available at the end of the evening, and I'm averaging 1.3 pounds lost per week. That's been consistent over 5 months. If my weight loss slows down at some point, I'll perhaps start leaving another couple hundred calories on the budget each night.

Also, the less weight you have to lose to get to a healthy number, the lower your expected loss per week should be. Don't expect to lose weight at the same rate when you have 5 pounds left to lose that you were losing at when you had 40 pounds to get rid of.

[bunkmungo]

Thank you so much for all of the helpful responses, everyone!! I really appreciate the explanations, and I am pretty new to this so it helps a lot!! 
I will probably try to leave a little extra calories over the course of the day to be safe and get the best results, but I won't let myself go hungry either 🙂

[josephz2va]

My advice is to go beyond the steps and focus more on Calories Burned. Caloric Burn Goal reachment will help lower not just weight but overall fat mass. I dropped 8% body fat in 7 days focusing on Elliptical Trainer only and reaching my calories burned goal of 3,700 per Trainer program on Fitbit (The Fitbit Premium Program).

[clo]

Thank you! Great article...so much to think about.