BMR and Starvation

Our BMR stands for Basal Metabolic Rate. It is the amount of energy (calories) that our body requires to function at complete rest. So if we were to lie in bed all day and not lift our head, it is the amount of calories our body needs to keep our heart pumping, our lungs breathing, our cells functioning. There are lots of calculators out there. My favorite is Scooby, because it figures out your TDEE as well.

So this is the base of our metabolism. It is based of height, weight, age, as well as body composition, and health status. The calculators are not perfect, as an actually BMR test at a University or health clinic would be more accurate, but it gives you a rough idea how many calories your body needs.

For example, my BMR calculation is 1487. So when many people say women can't go below the 1200 calorie mark, it is because most women's BMR is around that OR MORE and they don't want you to go under it.

If there is one thing I've learned over the past six months, is that our bodies are amazing. They can evolve and adapt to some of the harshest conditions. Extreme calorie restriction can cause your body to go into starvation mode.

 When in starvation mode our bodies can actually slow it's metabolism to help the body survive on less calories. So if my body requires 1487 calories to function, and I eat 1200, after a while my body is starving and will slow my metabolism as much as possible so that it can still function. So then my BMR could get down to 1000 calories or less because I'm only giving it 1200 and I'm still trying to be active and go about my day burning even more calories. Your body may tap into your fat stores to find energy, but it really wants carbohydrates and proteins too, so it will start taking away your muscles as well.

So now my metabolism is super slow, and my body is not functioning at it's utmost potential. Now working out is an awful experience, because I have no energy left over because my body is using what calories it is given just to function. So I'm miserable, tired, and irritable. Then I pig out on some cake or something. My body is SO HAPPY it is finally getting fed that it holds onto every last extra calorie and stores it for later.

So then you think...I gotta eat less, because I was eating 1200 calories, had a couple 1800 calorie days and gained weight so I need to eat 1000 calories a day and workout more. NOT A GOOD IDEA. You will either reach a breaking point and sabotage everything, or you will have an eating disorder. Not good at all.

This is why eating your TDEE is great, because it keeps your metabolism fired up by giving your body enough calories to meet your BMR as well as give you enough energy to work out and go about your daily activities. And you can still lose weight by just slightly reducing the amount of calories you take in, but never dropping them below your BMR.

I have lost 19.4 lb's total and (besides a few weeks at the beginning) I did it eating NO LESS then 1800 calories a day. I usually ate 1900-2200. I am a taller than average girl, but still. I did not need to eat 1200 calories to lose weight. And I did not feel extremely deprived or miserable. I was able to have energy to really push during my workouts, and I still feel like I could have a treat on occasion if I could fit it into my calories. I feel it had really helped me to be successful and lose weight, even though the process was slower, it was really worth it.