Fat loss or gain is relatively simple. That doesn’t mean it is easy. You may have heard that it all comes down to calories in versus calories out. While that might be true on the surface, there is a lot that can impact your likelihood of success. Let’s break it down.
Starting here: What is a calorie?
By definition it is the amount of energy required to heat up one kilogram of water one degree Celsius. You can think about calories as fuel for your body.
The physiological process for fat loss or gain occurs when there is either more or less energy (calories) consumed than burned in a day. Body weight is considered to be stable when energy in is equal to energy out. Consider the following energy balance equation:
TDEE = BMR + NEAT + TEF + EAT
The amount of energy your body burns in one day is equal to the total daily energy expenditure (TDEE). This value is important to be aware of for weight management. In order for fat loss to occur, your TDEE needs to be greater than the amount of energy consumed (calories). In order for fat gain to occur, TDEE is less than the amount of energy consumed.
So, what does all this mean for losing weight?
TDEE is composed of four variables that you can work with in order to create either a calorie deficit or surplus. The first and most common is BMR, which stands for your basal metabolic rate. This is equal to the rate of energy expenditure per unit time at rest. Think about it as the amount you would burn if you were to lay in bed all day. This number is the amount of daily energy your body needs just to function. It accounts for about 70% of your daily calorie burn.
Next up is NEAT, or non-exercise activity thermogenesis, which accounts for the energy expended for everything we do that is not sleeping, eating or exercise. This variable can be manipulated day to day and is roughly 15% of your total daily energy burn.
Third up is TEF, or the thermic effect of food, which is the increase in metabolic rate after ingestion of a meal. Yes, it takes about 10% of your daily energy needs to actually digest and process the food you consume! That leaves us with the last variable, exercise activity thermogenesis (EAT). This category accounts for about 5% of your daily energy burn and is the energy expended from exercise that you intentionally engage in.
OK, so now what?
Well, having a better understanding of these variables can provide a strategy for how you approach fat loss. NEAT and EAT are the two variables that can be manipulated to increase a calorie deficit. Think: how can you increase your movement throughout the day therefore creating more energy burn. Examples might include parking far away from the store to increase the amount of steps you take, getting up more throughout the work day, walking to the bathroom that is farther away, etc.
Ultimately, the more energy you burn or use in a day helps to create a calorie deficit that will allow for fat loss to occur. Keep in mind the less you move, the calorie deficit would have to be created by reducing the amount of food you consume.
As for me and my clients, we aim to lose fat while still being able to eat as much as possible. There are times when a greater calorie deficit is necessary, but at the end of the day you don’t want to be miserable during a deficit. You might be less likely to stick to it and see the progress you are looking for. This doesn’t mean it will be easy. You will still have to put in the work and make some sacrifices in order to reach your goals.
At the end of the day, having an increased understanding of these variables will help you better approach your own fat loss or fat gain journey. You will have to develop discipline and continue to learn more about what is optimal for your own body’s needs. Remember, if it were easy, everybody would be doing it. Just take it one step at a time – you got this!