What is a Calorie Deficit?
In my last blog I explained to you exactly what Calories are and how they are used by the body. Today I'll talk about 3 terms you may have heard during the course of your Fitness Journey, these are Calorie Deficit, Calorie Surplus and Maintenance Calories.
What exactly do these terms mean? I'll explain.
Simply put, if you’re trying to gain weight and fat, lose weight and fat or simply stay where you’re at with your weight, you need to control and monitor your calorie intake. Gaining weight requires that you consume more calories than you burn and losing weight requires the polar opposite, burning more calories than you consume. Eating roughly the same as what you burn is called maintenance and your weight should stay relatively stable. Your calorie 'balance' (the difference between what you eat and what you burn) will determine your weight, there is no way around it, being in one of these 3 states will effect your bodies weight.
A calorie deficit is a state in which you burn more calories than you consume. Losing weight and dropping fat requires a calorie deficit. When you enter this state, your body needs to somehow make up the difference of what you burn during activity and what you eat. If you’re burning 2,500 calories per day and eating 2,000 calories, that 500 calories needs to come from somewhere. That somewhere is your body fat. Body fat is stored energy that was created in times of calorie surpluses (read below). When you are in a calorie deficit, your body begins drawing upon those fat stores for energy, which over time, causes weight and more importantly, fat loss.
How Much of a Deficit?
This is always the main question. "How much of a deficit do I need to be in to lose weight and body fat?"
The answer is simple, even a 100kcal per day deficit would result in weight and fat loss, though this would be a slow, yet very healthy way of doing it. When you have a fair amount of weight and body fat to lose you can be more aggressive with that deficit and I'd say a Maximum of 750kcal per day which is at the extreme end of weight loss would be as low as you would ever need to do. A more realistic and easy to manage number would be 500kcal per day.
Why 500kcal? 1lb of fat is equal to 3500kcal (roughly) so consuming 3500kcal will result in a 1lb gain and burning 3500kcal will result in losing 1lb. So let's say you want to lose 1lb per week, which is a healthy number to aim for. You would need to be in a deficit of 3500kcal over the course of the week, there are 7 days in a week, so divide 3500 by 7 = 500kcal
To lose 1lb per week you'd need to be in a 500kcal per day deficit.
A Calorie Surplus is the opposite of a deficit. Eating in a surplus will result in weight and body fat gain, but the reason many people go into a calorie surplus is to build muscle.
While calories directly don't build muscle, they provide you with the energy to build more muscle, more calories = more energy to train harder for longer and more calories result in better recovery, especially calories from Protein.
Getting into a calorie surplus is such an easy thing to do if you are not mindful of what you are eating, especially with low volume, high calorie foods ie, donuts, chocolate etc, they are very easy to consume and not fill you up or satisfy as they are low volume so the calories mount up very easily. Similar to the 500kcal deficit, if you are in a 500kcal surplus per day every day then you'll gain 1lb of fat per week.
So lets say you are the average female eating 2000kcal per day for maintenance, if you dropped to 1500kcal per day you'd lose 1lb of weight / fat per week, but going into a surplus of 500kcal per day up to 2500kcal would have you put on that 1lb. So imagine if you were hitting 3500kcal per day, which is VERY easy to do, you are looking at 3lb per week and nearly 14lb (1 Stone) Per Month. This is why its important to track your calories if you have a specific goal in mind.
Many people Especially guys tend to go overboard when it comes to going into a surplus, they mainly do this as they think the more they eat the more they will grow, more energy = better training = more muscle!! Right?
Not quite. The body only needs a slight surplus of a maximum of +300kcal in order to help you build lean muscle, if you eat more than the body needs, its simply stored as body fat, the more fat you have then the harder you'll have to work to get it back off when it comes to it.
Other Terms for Deficit and Surplus
Some other terms you may have heard when it comes to deficit and surplus may be Bulking and Cutting or Shredding. You may hear these terms if you are around the Fitness / Bodybuilding Competition circuit, they are words that simply describe Building Muscle (Bulking) and Dropping Fat (Cutting Fat)