3 Reasons You’re Gaining Weight in Calorie Deficit (And What To Do About It)

Are you gaining weight even though you are in a calorie deficit?  Here are the 5 reasons why it's happening and also what you need to do about it. 

When you're on a diet and working so hard to cut your calories, it is very frustrating when the scale goes up.  Especially when you are making sacrifices and avoiding certain foods to maintain a calorie deficit and all of your sacrifice feels like it's for nothing when you gain weight.  Believe me, I know exactly how you feel.  

You are going to learn the 5 reasons why your are gaining weight in a calorie deficit.  And, you're going to learn what to do about it so all your hard work doesn't go down the drain.  

This  post is all  about what to do if you are gaining weight in a calorie deficit.  

DISCLOSURE:  This post may contain affiliate links which means if you click on a product and make a purchase I will earn a small commission.  I only recommend products that I truly believe are great so you get an awesome product and I get a small commission.  It's a win-win.  

1.  You're Not Actually In A Calorie Deficit

The first reason you are not losing weight when you are in a calorie deficit may seem fairly obvious but it's usually the culprit (and I've had this happen too).  The hard truth is if you've been on a diet for more than a couple weeks and you aren't losing weight (or worse gaining), you are not in a calorie deficit. 

If you burn more calories than you eat, you will lose weight.  But wait, you are thinking?  I have been so good on my diet, I must be in a calorie deficit.  

Because each of us is different, there is no magic calorie number to eat every day to ensure that you are in a calorie deficit.  For me, I have a relatively small frame (I am 5'4").  My husband by contrast is 6'4".  Even if we never moved all day, my husband would burn way more calories than me.  There are days when I am extremely sedentary and I will only burn 1600 calories.  So, if I were to eat 1600 calories, I actually wouldn't be in a deficit at all.  And, if I ate the recommended suggested calorie intake for a woman (around 2000 calories) I would actually be eating more calories than I burned and gain weight. 

For us smaller framed people, the calories can be very important.

Solution 1: Counting Calories!  

It's old school but it works.  In order to know if you are in a calorie deficit you must know how many calories that you are eating.  It's basic and simple but it works. 

Often times people will come up to me and say, "I'm eating perfectly on my diet and can't lose any weight."  To which I will ask, are you logging your food and tracking your calories?  Almost 100% say no.  

Every time I have been successful in losing weight, I have been very diligent about tracking my calories.  Back in college I had a calorie count book and used a piece of paper.  Now, I use a free app which I am sure you have heard of, called Myfitnesspal.

I am constantly surprised by how resistant people are to logging their food and tracking their calories.  The fact of the matter is, you have no way to know whether you are in a deficit unless you know how many calories you are eating each day.  

A couple years ago, I was feeling like I was "a freak of nature."  I was convinced that I was eating far fewer calories than I burned and was completely mystified why the scale wouldn't go down.  Then I started honestly tracking my calories.  I realized that I while I thought I was consuming 1200-1400 calories a day, I was actually consuming closer to 1700-2000 calories per day.  This was in line with what I was burning so it made sense that I wasn't losing weight.  

In order to lose weight it is really all about calories in vs. calories out.  Often when people are not losing weight they aren't even keeping track of all their

Solution 2:  Figure out how many calories you burn each day!

Figuring out how many calories you eat each day is the first step to the process and where most people stop.  But, you need to also determine how many calories you burn each day. Here are three ways:

Best:  The best way I have found to determine how many calories you burn is by using the calories burned feature on Fitbit.  This is what I use to determine how many calories I burn each day.  I love it because it is personalized to me and I find that when I eat approximately 1000 calories less than what I burn (according to my fitbit) I consistently lose weight.  

If you don't have a Fitbit, go to "goals" in Myfitnesspal and fill in your starting weight and goal weight and how fast you want to lose weight and it will give you a suggested calorie goal each day.  Tip:  Set your exercise to sedentary or light so that it doesn't overestimate your daily calorie burn.

Third,  use an online daily calorie calculator such as the one below.  This calculator is based on the Harris-Benedict equation.  Calculating your daily calories based on your data because it gives you daily calorie estimates based upon how aggressive you want to set your weight loss goal.

2.  You're Not In As Much Of A Calorie Deficit As You Think

This is very similar to reason number one but is actually the most common reason.  What usually happens here is that you are actually logging your food but you are not logging all your calories.  

You logged your lunch but didn't log the two chicken nuggets that you ate off your son's plate.  You logged your dinner but not the cheese that you ate while making dinner.  You logged your planned snack but didn't log the pretzels that you ate on the car ride home from the store.  You logged one glass of wine but not the two that followed, etc. etc.  

As a result, when you look at your food log it looks like you are definitely in a calorie deficit but all of the things that you didn't log put you over your limit.  And, of course our memories are short - we don't remember all those extras that we ate throughout the day we just see our perfect food log and think "what is wrong with me?"  

The truth is, nothing is wrong with you.  You are just eating more calories than you burn.

The other problem is related to when people over estimate their daily calorie burn.  This is why I don't think it's an exaggeration to say that my Fitbit was crucial to my weight loss.  My calorie burn can fluctuate quite a bit.  On days where I am very sedentary, do not exercise and binge watch netflx on the couch, I can burn as little as 1600 calories.  On the other hand, on the days that I am very active and have a heavy workout I can burn up to 3000 calories.  

So, if I was burning 1800 calories per day and eating 1500 calories per day, that is good but it is going to take a little bit for the scale to start showing anything,  

So, if I am burning 300 calories per day  it's going to take about 11 days for me to lose a pound on the scale.  But what usually happens is, since we have over estimated how much of a deficit we are in, when we lose one pound in two weeks we don't see that as a victory and we go off plan out of frustration and throw all our hard work down the drain. 

Or, we don't even get to the eleven day mark.  After seeing nothing change on the scale for 10 days we think "well this clearly isn't working" and go back to our old ways.  

You can see that by not knowing how many calories we are actually eating or how many we are burning it is easy to think that you're not losing weight in a calorie deficit - when in actuality you are!

3.  You Are Retaining Water

If you just started a new diet and also started to increase your exercise routine your body may be holding on to excess water.  I'm sure that there is some very scientific explanation as to why this happens but I always just think of it as my body is in shock from the increased activity and doesn't know what's happening so it hangs on to extra water.  

You ate a high sodium meal.  Sodium (aka salt) makes our bodies think that it is dehydrated and so it hangs on to every drop of water it can.  This makes the scale go up and also makes our clothes feel tight.  This will happen even if you are in a calorie deficit but it is temporary.  

If I know that I am in a calorie deficit and the scale unexpectedly goes up, I first look to myfitnesspal diary from the day before.  Often times, I will discover that I had a high sodium day the day before (a typical sodium day should be around 2000 mg or less).  When I see this, I know that it is temporary and as long as I decrease my salt and keep in my calorie deficit, the scale will start going back down shortly.  

Finally, another reason that you might be retaining water is because of your menstrual cycle.  Most of us naturally retain water in the days leading up to our period.  If you have an unexpected jump in the scale check to see where you are in your cycle and that may explain it. 

If you are having a lot of water retention you can purchase an over the counter diuretic or call your doctor and ask for a prescription water pill.  I have a water pill from my doctor and I also use these drops from Amazon if the retention is really bad.  I like these, they seem to help and they have a good taste - like honey.  

Solution: If you are retaining water, know that your body will eventually release the extra water.  In the meantime, cut down your sodium and drink extra water so your body knows it is hydrated and doesn't think it needs to hang on to every extra ounce.