Calculating Calorie Requirements For Fat Loss

As we have come to learn, we essentially need a caloric deficit before we can even begin to think about fat loss. But how do we go about creating this calorie deficit, based on our body statistics? This article seeks to help you make some headway in that area!

The Energy Balance: Calorie Input vs Calorie Output

Calories are chemical energy; and not only are Calories chemical energy, but they are a measure of potential (stored) energy. All foods we eat are basically stored chemical energy. When we "count calories", we are basically calculating the chemical energy stored in the food. For example, 1 gram of carbohydrates might contain 4 calories.

Calorie input involves the intake of this chemical energy found in our food. This occurs during the digestive process, starting at the mouth. Calorie output involves taking the energy from food and burning it, thereby converting it into a form usable by our bodies. This occurs at a cellular level.

Each of us have a unique energy requirement based on body stats such as our current gender, age, height, weight, daily activity level. And based on this energy requirement, we identify how much calories we intake. The energy balance plays a significant part in determining whether you will gain fat, maintain fat, or refrain from fat gain:

Caloric Input > Caloric Output: Body Fat Level Increased
Caloric Input = Caloric Output: Body Fat Level Maintained

Caloric Input < Caloric Output: Body Fat Level Decreased

The Components Of Calorie Output

The human body is always burning calories one way or another, whether we are active or at rest. Some of these ways are:

Basal Metabolic Rate (BMR): energy expended (burned) from normal biological functions

Thermic Effect of Food (TEF): energy expended from digesting food

Thermic Effect of Activity (TEA): energy expended from formal exercise workouts or sporting activities

Non-Exercise Activity Thermogenesis (NEAT): energy expended from performing non-exercise physical activity. These are activities which are not strenuous or physically intense as formal exercise, and range from normal everyday activity to small or limited movements of the body (e.g., performing house chores, office work, stretching, etc.).

Caloric Output is the sum total of all energy burned on a daily basis, and is more appropriately called the Total Daily Energy Expenditure (TDEE):

Caloric Output = TDEE = BMR + TEF + TEA + NEAT

Therefore:

Caloric Net Balance = Caloric Input - Caloric Output

Is the same as saying:

Caloric Net Balance = Caloric Input - TDEE

When your caloric input is approximately the same as your TDEE, you are said to be at maintenance.

When your caloric input exceeds your TDEE, you are said to be at a surplus.

When your caloric input reduces below your TDEE, you are said to be at a deficit.

So when you burn (expend) more energy than you intake (eat) on a daily basis, the negative caloric net balance creates a deficit. A negative caloric net balance then leads to fat loss.

Knowing Your TDEE Maintenance Requirements

In order to begin calculating a caloric deficit, you need to identify your calorie intake needs based on your body measurements and activity level.

The websites listed below provide a great way of calculating your Maintenance Requirements. Be accurate as possible when entering the required data:

Fit Watch
The Calorie Calculator
Free Dieting Calorie Calculator

Considering that strength training and cardio will be involved in your fitness plan, these will obviously play a critical part in determining your activity level. It is therefore important, based on your workout quantity and schedule, to choose an appropriate Activity Level. It should be noted that it's not possible to simply categorize your activity level based on the website definitions alone. For instance: on an average week, I workout at the gym 3 times, which more or less puts me in the category of Moderate Activity Level. HOWEVER, I usually spend over 2 hours in the gym on each workout day. I also lift heavy and perform multiple exercises per gym session. That's why I don't select Moderate Activity Level: I choose Very Active. This is an ideal selection as it is in alignment with my exercise output.

Pay attention to not only the frequency of your exercises, but also to the intensity and duration of your workouts to better assess your Activity Level.

Try weighing yourself with limited clothing on; if you have access to a scale in the comfort of your home, try measuring your weight nude. This allows for more accurate measurements of your weight. Measuring with clothing on throws off your actual readings, causing errors and can lead to incorrect calculation of calorie requirements. An electronic scale provides better accuracy and easy-to-read results.

Be also mindful that with each step in your fat progress, as you continue to lose fat, your TDEE requirements change (get lower). Keep these websites at hand, as it will become necessary to recalculate your values periodically, as much as a weekly basis.

Now we can go into calculating your calorie deficit.

Calculating The Calorie Deficit As A Percentage Of Your Maintenance Requirements

Based on the figures you punched in for your body measurements and activity level, you'll arrive at the required caloric intake that will keep your body's energy balance at maintenance: that is, Caloric Input = TDEE. At this point, your fat stores are not accessed; what we want to do now is calculate a deficit to begin burning them.

It's nearly impossible to get exact figures when it comes to calories, so it's always more reliable to go with close estimates and ranges. So what we do is create a deficit range. An ideal range is between 15% - 20 % deficit. Creating a caloric deficit as a percentage of your estimated calorie intake based on your TDEE is better than just cutting calories to an arbitrary figure (e.g., cutting 500 calories out of your intake). It is also a more personal calculation. My calorie deficit may need to be smaller than yours, and vice versa. My calorie deficit may need to be between 2700-2900 calories, while yours needs to be 2200-2500 calories.

Whatever calorie intake value you got from the website, multiply it by 0.80 (the 20% deficit) and 0.85 (the 15% deficit)

Example:

If Jim's calorie intake (based on body measurements and activity level) needs to be (approximately) 2500 calories:

15% deficit would be 2500 x ((100-15) / 100) calories = 2500 x 0.85 calories = 2125 calories;

20% deficit would be 2500 x ((100-20) / 100) calories = 2500 x 0.80 calories = 2000 calories

Therefore, Jim's calorie deficit range is going to be 2000 - 2125 calories consumed daily based on his TDEE. Jim is going to be working out in the gym and expending energy, while at the same time eating below his caloric output. This calorie range is going to allow him to be in a deficit in order to tap into his energy stores (burning fat). 


Due to the fact that you are using a range of values rather than a specific value, you can consider the option of cycling your calories, as discussed in previous articles here and here, while maintaining a calorie deficit range between 15%-20%. Also include a day to eat at maintenance, as advised by the articles.

Recalculate your caloric deficit range with each reduction in fat and weight.

Conclusion: 

Calorie Tracking Leads To Better Fat Loss Results, But Do You Have To Count Calories Forever?

Absolutely not. However, calorie tracking is as critical to the fat loss process as much as creating the deficit itself. You need to at least make estimates of how much calories you need (to consume from food, which goes towards being burnt and converted for energy) on a daily basis, and from there determine how large a deficit is needed. These figures are never going to be 100% acccurate, but it is always better to make best-guest estimates.

Naturally, obese people can afford to create huge deficits due to the fact that they have a higher body fat percentage (lots of fat stored on their body) and can therefore have a larger negative energy balance daily (20% - 25%). As a person loses more fat, the smaller their deficits should be. Creating too large a deficit can lead to negative impacts such as fatigue and muscle loss. Having too large a deficit can also give rise to fat loss plateaus.

Thanks for reading!