You've asked that question to yourself multiple times. Remember never having to worry about your weight when you were younger, but as soon at you hit your 20s it felt like everything was losing day, and not in a good way.
So, maybe your metabolism is slowing down?
Well, first, you never burn the same amount of calories every day, you never only burn 2000 or 1500 calories, our bodies and metabolism as flexible. Our calorie burn changes depending on our hormone levels, our own food intake, activity, if your sick or healing. All of these things play a role in what makes up and what our metabolism is like.
That's why I don't like calorie calculators, but that topic is for another time.
Our metabolism changes. Every day. Every second of our lives, how we run is a little bit different.
And, our metabolism can very easily slow down. It's not like it just slows down once you hit 30 or 40 or 50. Our bodies don't realize what age we are exactly, so it definitely isn't saying "hey, I just turned 30 today, time to become lazy!" Nope, that's not it.
What actually makes our metabolism change the most, besides if we are sick or changes in our hormone levels, is our food intake. We can handle a day or 2 of under-eating without making our metabolism freak out.
But what our bodies cannot handle is an extended period of time where we are under feeding ourselves. We may be burning 2000 calories a day, but your taking in 1200 calories. At first, you'll see a weight loss and it will seem like everything else is staying the same. After a while though, at a low calorie intake, our bodies start to know that it will be under-fed and that it needs to start getting creative with how we use our energy and how we function every day.
After a while of under-eating, you may start to have stomach and bowel issues. This can show up as frequent gas, nausea, constipation, or diarrhea. We don't have enough energy as we need, so our bodies must cut corners with making hormones and other secretions to help with digestion.
Prolonged under eating will also have the body make changes on a cellular level. Our mitochrondia, the powerhouse of the cells, can make changes in the processing of information and function of the cell itself.
Our bodies stop making certain hormones or won't make enough of them to trigger a certain response. Gherlin is the hormone that helps to signal that our body is hungry, when we are in "starvation mode" our bodies will stop making that gherlin so you don't feel hungry any more. Leptin is what makes us have that full feeling, that also becomes diminished as the restriction continues.
You will stop seeing changes in your weight, and in your muscle mass as you get deeper and deeper into extended restriction. In essence, our bodies are kind of shutting down a little.
Going on strike because it's not getting what it wants. That's why we CANNOT be a calorie deficit for many months and years at a time. We are not meant to live on 1200 calories a day. I have talked to many of you and many others, most have said that you have been trying to lose weight for years. One person said 20 years... So next time you consider cutting your calories even lower or continuing/choosing a new diet to be on, why don't you consider a diet break? Add some food back in and give your body a rest. Everything that is suppose to happen will start to come back again and you'll begin to feel good.