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5 Hidden Reasons You’re Gaining Weight While Breastfeeding

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Not losing weight (maybe even GAINING) while breastfeeding is a surprisingly common, yet frustrating, problem that new moms face.

If you’ve experienced this, it probably left you feeling a little surprised and confused. After all, isn’t breastfeeding supposed to help us lose weight? That’s what everyone says, right?

You almost expect the pounds to just melt right off!

It can be extremely disappointing when that doesn’t happen– When quite the opposite happens.

After all (I get it), you just want to fit into your old pre-pregnancy clothes again.

There are several possible reasons for weight gain while breastfeeding, including lifestyle changes and shifting hormones.

Related: 17 Helpful Tips for Losing the Baby Weight

Do women normally gain weight if they’re breastfeeding?

You may wonder whether it’s normal to gain weight while nursing or whether you’re experiencing an issue that needs to be addressed.

There is a common misconception that if you breastfeed you’ll quickly lose the extra pounds you put on while you were pregnant. However, this isn’t always the case.

Every woman’s body behaves differently from the next, particularly when hormones are involved. While some women do experience speedy weight loss when breastfeeding, this isn’t as common as you might think.

The overall thing to bear in mind is not to worry because it can be completely normal to not drop a ton of weight while you’re breastfeeding.

5 Hidden reasons you’re gaining weight while breastfeeding

Many women do gain a few extra pounds during this time. Here are 5 potential reasons why.

1. The prolactin hormone

Prolactin is the hormone responsible for making a woman’s body produce milk. It’s released every time you feed your baby.

Not only does prolactin cause lactation, it also boosts your appetite.

As a natural result, you may eat more calories than you actually need (because you’re hangry!), which can result in weight gain.

However, the good news is that this phase won’t last forever.

Once you are between months 3 and 6 of breastfeeding, it may become easier to maintain or even lose weight because this is when milk production is still high but feedings tend to be more spaced out. Therefore, prolactin is released less often.

2. Your less-than-stellar eating habits have carried over from pregnancy

A lot of moms believe they need to eat twice as much as usual during pregnancy. You know the saying, “eating for two.”

Yet, although this is an appealing idea to anyone who loves food (raises hand), it’s a completely wrong concept.

During pregnancy, you only need around 340 additional calories during your second trimester and only an extra 450 during the third trimester, and it’s best to gradually increase your calories.

If you eat more than the recommended amount, there’s a good chance you will gain more weight than you need to during your pregnancy.

So, basically, if you are used to eating certain foods or larger portion sizes and you continue these eating habits, it may contribute to more weight gain while you’re breastfeeding.

3. You need more or better sleep quality

We all know that poor sleep quality sleep isn’t healthy.

It’s understandable, though, that poor quality sleep just isn’t a choice for new moms. You are probably grasping at straws here– Doing your best to get enough sleep, but it’s still hard to pull off when your little one is waking up every couple of hours.

My best advice is to hang in there and do your best. Learning how to get your baby to sleep more and reading a few tips to make life easier with a newborn are a couple things that can help you get more rest and stress less.

But what does sleep have to do with weight gain, anyway?

If you fail to get sufficient sleep, you’re boosting the hunger hormone, Ghrelin, which increases your appetite substantially, causing you to consume even more food than usual. There’s also another hormone called leptin, and you have less of this when you are sleep-deprived.

A study discovered that those who fail to get sufficient sleep will typically seek out higher calorie meals so they can satiate their hunger, and this just adds even more fuel to the fire!

Don’t throw in the towel yet, though. There’s no shortage of filling and healthy foods which won’t result in you gaining a lot of weight.

If you’ve been eating a lot of junk food and empty calories, you may need to change the types of foods you’re eating.

Think nutrient-dense whole foods like oats, Greek yogurt, berries, or eggs. These are all good options to help you to feel full when hunger strikes.

4. You’re not as active as you may think

Another very possible reason you could be gaining weight while breastfeeding is simply because you are not as active as think you are.

While it may feel like you’re racing around the house all day, in reality, you may not be getting in as many steps as you think.

An easy way to keep track of your steps (if you don’t own an Apple watch or want to have your phone on you all day long) is to invest in an activity tracker such as a Fitbit.

I purchased my first Fitbit shortly after my second baby was born, and it was very helpful for figuring out how active I actually was. And let me tell you, it wasn’t nearly as active as I thought I was.

If you’re barely getting 4,000 steps per day, then you’re not burning very many calories. Therefore, the amount you can eat to maintain your weight will be much less than a mom who is more active.

5. You’re stressed

It’s not too surprising that, when you take into account sleep deprivation, hormonal changes, and the responsibility of caring for a new baby, your life at this time can be quite stressful.

If you’re under a considerable amount of stress, the body produces more cortisol. This is the hormone that is linked to stress and overeating.

There are so many different self-care activities you can try to help you de-stress. One of my favorite ways personally is to listen to or watch ASMR.

But that’s just one way to de-stress. You could also:

  • Journal
  • Color or draw
  • Listen to your favorite music
  • Take a walk outside
  • Read
  • Stretch
  • Meditate or try breathing exercises
  • Take a break from social media
  • Exercise
  • Take a long shower

See? So many ways. Your mental health is worth it!


Try not to get too discouraged if you’ve found yourself gaining weight while breastfeeding. This is very common, despite what you may have heard from other moms.

Hopefully these reasons have helped you pinpoint what could possibly be going on. If not, this is only a temporary chapter in your life as your baby won’t be breastfeeding forever.

Try to enjoy these precious moments with your tiny baby as much as possible!