In science, there are very few absolutes and a lot of variables. Most of the things we know either depend on numerous other factors to work predictably or don’t have that much scientific backing.

One law, however, is as valid as gravity is. We can argue with it, try to reason with it, or seek an alternative. But, just as the invisible force of gravity keeps us planted on this blue planet, this law also predicts how our bodies will change over time.

So, what am I talking about?

The Law of Thermodynamics

We can buy and consume all of the latest fat-burners, diets, and workouts. Most people do. But without understanding and respecting thermodynamics, our efforts will be futile.

Thermodynamics, as it relates to human metabolism, states that the body cannot create or destroy energy but can only convert energy from one form to another. So, what does that mean?

Well, for one, it means that our metabolism can only convert the calories we consume into heat transfer, work, and stored fat. It cannot destroy that energy, and it cannot create more energy than it has available.

Secondly, this gives us a good idea that the number of calories we consume every day is the best predictor of weight change (or lack thereof).

Let’s see how that works in the real world.

Basal Metabolic Rate and Total Daily Energy Expenditure

Total daily energy expenditure (TDEE) refers to the number of calories your body burns each day from walking, talking, eating, digesting food, exercising and your body performing its many biological processes that keep you alive and healthy.

Basal metabolic rate (BMR) refers to the number of calories your body burns at rest, to keep its systems going, even if you don’t move a single muscle all day.

For anyone interested in counting calories to achieve a specific outcome (be it muscle gain or fat loss), they need to know their TDEE – that number is individual to you and can change drastically from day to day and over time. Without that, you could count all the calories you want, but that won’t matter.

So, you ate 2700 calories today. But what’s your TDEE? Some people gain weight, and some people lose fat very quickly on that many calories.

This is a big reason why cookie-cutter diets don’t work well. An active six-food-something guy in his twenties who weights upward of 200 pounds will have drastically different calorie needs than a 5’5” sedentary woman in her forties who weighs 120 pounds.

As a general rule, the more active you are, the more muscle you have, and the younger you are, the higher your TDEE will be. This is why many people tend to gain weight as they age – they lose some muscle mass and become less active, but their calorie intake stays the same.

Calories In vs. Calories Out

Many dietitians and fitness gurus out there hate the term calories in vs. calories out (CICO). They reason that calorie quality is what matters, not quantity. To be sure, the quality of your diet matters for general health and body composition, but it’s the number of total calories you consume that dictates weight loss, weight gain or weight maintenance.

Say that you’re an average person with an average activity level. Your TDEE is 2500 calories. If you eat 2000 calories per day, you’ll lose weight at a steady rate. If you eat 3000 calories, you’ll gain weight. And if you eat roughly 2500 calories, you’ll maintain your current weight over time.

It doesn’t matter if you exclusively get your calories from junk food or adhere to a nutritional plan made by a professional and filled only with whole, nutritious meals.

To be clear, I’m not saying that diet quality doesn’t matter. It does. But don’t expect to lose weight just because you’re eating ‘clean,’ unless you’re also eating in a caloric deficit. If you track your calorie intake and adhere to one of the three numbers from above, you’ll most reliably see the progress you are looking for.

Some people are naturally skinny and want to pack some mass, so eating in a caloric surplus is a good idea for them. Then, there are those who want to lose weight. For them, eating fewer calories than they are burning helps them shed some fat. And finally, there are those who like themselves for what they are, and they want to maintain. So, taking the middle road is what they need.

But, in any case, whether you like it or not, it’s calorie quantity that dictates change. You need to find what works for you, as an individual.

Calorie Counting: Good or Bad?

At this point, you’re probably wondering whether counting calories is good or bad. After all, the number of calories you consume is the most significant predictor of weight change.

No one answer will work well for everyone because we are all different. Some people have more finely-tuned hunger signals and can do great without tracking calories because they know when to stop eating. Then there are those people who, unless instructed, cannot stop eating until they are completely stuffed.

Scenario 1: Who Counting Calories is Good For

Counting calories is suitable for two types of people: those who can’t help but overeat and those who consistently undereat.

For these people, adhering to a specific calorie range is good because it will help them improve their body weight for the better. Underweight individuals will gain some weight, become healthier, and feel much better. Overweight people will lose some of the excess fat, also improve their health, and feel drastically better about themselves.

Both types of people will also improve their appetites and will understand hunger signals and satiety better.

Counting calories is also good for more athletic individuals who want to drop some excess fat. Being accurate with their calorie intake will allow them to set a moderate caloric deficit and lose fat at a steady rate while preserving their muscle mass.

Scenario 2: Who Counting Calories is Not So Good For

Some folks have more finely-tuned hunger signals. Maybe they are genetically gifted, or perhaps their upbringing has affected that. They know when they are physically hungry (not just bored) and, more importantly, they know when to stop eating.

Such individuals are at a healthy weight and body fat percentage and don’t have to think twice about their eating habits.

If they want to gain some muscle, they don’t need to calculate a specific caloric surplus and adhere to it. All they have to do is sneak in a bit more food each day, and they’ll get the job done. On the other hand, if they want to shed a bit of fat, they can reduce their food intake a bit and watch as they get leaner.

These lucky few don’t need to complicate things by calculating TDEE and counting calories.

Which Category Do You Fall Into?

You need to be honest with yourself. If you fall into scenario two, that’s great. Keep doing what you’re doing, eat in accordance with your goals, and you’ll do great. The intuitive eating approach will do just fine for you.

But if you can’t honestly tell yourself that you know the difference between physical hunger and boredom, and if you don’t know when to stop eating, then you’d do much better with a more exact approach.

And if you fall into scenario one, don’t despair. Calorie counting is an excellent tool you can use to become more in-tune with your hunger and satiety signals and then gradually start eating intuitively.

Over time, you’ll learn how much food you need to eat, and you won’t have to rely on counting every last calorie to achieve your goals.

What to Do Next

Both counting calories and eating intuitively have their benefits and drawbacks. And no matter which route you decide to go, there will be bumps in the road.

Here, at Fitlov, we strive to smooth out these bumps by providing our customers with the best personal trainers in Dubai.

Our app allows you to find and book top-rated personal trainers in your neighbourhood.  Everything is custom-tailored for you based on your situation, ability to train, and personal preferences.

So, if you’re looking for a fitness trainer in Dubai, Fitlov is for you. What are you waiting for? Download our app and get started!

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