I am going to try my best to stick to one path on this blog as actually when it comes to this subject there is so much to discuss. For the purpose of this blog we are going to look at the how lowering calories too low can have a negative effect and impact on your body’s processes. So say we were to have someone consuming 1000-1200 calories a day because they are dieting, been told to by their PT, friend etc (This is where I have to hold back and stay on subject) . Everyone’s bodies work differently but lets use mine as an example. So my TDEE is 2106, this means that my body burns around that amount of calories a day. This includes the following processes that add up to creating my TDEE :
BMR: Basic metabolic rate
NEAT: Non exercise activity thermogenesis
TEF: Thermic effect of food
EAT: Exercise activity thermogenesis
You don’t have to think too much about it all just think TDEE as a whole. Now if I reduce my calories by such a dramatic amount many things will happen, Here are some below to have a think about.
The body will slow down metabolic processes to keep fat for survival (Our bodies are made to keep us alive and they are extremely good at doing this) this is called adaptive theromgenesis, this also impairs protein synthesis, we don’t want to slow down our metabolism we want to make our body work harder as we then burn more calories.
TDEE will decrease, if it decreases this means you are burning less calories throughout the day. Lowering you caloric output and consuming less your body will want to preserve stores so the NEAT, EAT and BMR will all decrease
Alongside point 2 multiple endocrine adaptations occur. There will be a decrease in circulating thyroid hormones, testosterone, leptin, insulin and IGF-1. An increase in catecholamines, glucagon and ghrelin.*ref ACA
The body will shut down the reproductive system as the body does not need it for survival when trying to spare energy for vital organs. This can cause long term issues in females and males and for those who want children I am sure this is not what you want to be doing.
As testosterone drops the ratio of estrogen will go up along with water retention particularly extra cellular (outside of the cell), this will also increase plasma volume (One of the reasons weight goes up during particularly the mid luteal phase of menstruation). This may offset potential scale weight loss despite the body still actually losing mass from lean and fat compartments. This can then make you want to chuck it all in and go back to old ways, which then makes you believe there is no way you can lose fat and feel good.
They are just some reasons why having a ridiculously low caloric intake are not good for you. This is why I am not a fan of the ever so popular trends/diets out there. People do not understand the physiological and psychologically affects that they can have on people and a lot of it is all about making money. It is time to start thinking about yourself and your body, understanding your body and doing what is right for you. To work out your own TDEE you can do it here https://tdeecalculator.net/This can range for every individual, the basics of fat loss is all about creating a calorie deficit. If you need help or advice please contact me, I am more than happy to help in any way I can.