The sad truth of the fitness and weight loss industry is that we (Anyone who tries to teach others) have a habit of vastly over simplifying things. This vast over simplification leads to some common misunderstandings. I am guilty of this type of misconception. When it comes to calories. Calories are not calories. A calorie is not a calorie out. But why is this true? This is why we have the endless debate of calories in vs calories out.
The Fact of the Matter – A Calorie is a Calorie
Confused yet? You should be. The first point is, a calorie is a calorie.This is a fact. Energy can not be created, nor destroyed. This is a fact. When it comes to a calorie, yes, a calorie of candy is the same as a calorie from an apple. Which is what we discuss in the article on What is a Calorie. At the same time, a calorie is not a calorie, when it comes to your hormones and how your body handles the calories consumed.
See, your body is like an automobile. Your automobile has some requirements to move. It requires gasoline, oil, break fluid, transmission fuel, etc. Your automobile also has a preferred fill amount. How much it wants to have to function optimally. When you look at it that way, calories are to you as oil is to an automobile. You can put different grades of oil into your automobile and it will function properly. It can run on oil no matter what grade or brand you select. But there is a difference between 5w – 30 and 10w – 40. You can overfill your automobile will oil.
When overfilled, your automobile will run less efficiently and will burn oil. You put cheap oil in your automobile, and it is less efficient. Your automobile prefers the right grade of oil for it’s engine type. Your automobile prefers the right amount of oil for its capacity. Just like your body, run out of oil long enough and your engine will cease – it is effectively dead.
The Paradoxical Analogy of Calories In vs Calories Out
I hope you follow my horrible analogies so far. Your body needs so many calories to function. It uses a set amount of calories as a rule. This is where I propose (And most regurgitate) that a calorie is a calorie. For weight loss, this is true. You need to burn more calories than you consume to lose weight. Your body wants to work at this perfect balance – just like an automobile wants the right amount of oil.
But then we decided to start using synthetic oil. And wouldn’t you know, synthetic was hyped as being better than the old oil we put into our engines. For a while, this was true. We kept designing newer engines which required synthetic or high performance oil. See where this is going? Some of us who have an engine which is higher powered, require synthetic fuel to function properly.
This is why a very active individual, or someone with a fast metabolism, can eat anything all day long and not gain weight. If that person does not eat junk they seem always hungry and lose weight. The problem is, our fuel is designed for high performance engines – the anomaly. The Gatorade you drink after the gym is fine when you are 18 and just spent three hours on the treadmill. When you are 45 and jogged for fifteen minutes? Not so much.
Author’s Note: I know, I use car analogies too often.
Then we come to a regular engine which is old. Sometimes you fill it with too much oil. Sometimes you do not have enough oil. Its body is rusting. The pistons have wear. You have replaced the alternator twice. The suspension is gone. This is your typical ‘knee replacement with high blood pressure’ person. Something has been replaced, and nothing is brand new. Your engine does not need high performance oil. It does not need synthetic oil. It does not need more oil. It does not need less oil.
The dip stick has wear on it from the years. You are not positive what full is. Plus, your engine burns oil and has a leak so you can never be too sure. When this happens to your automobile engine, what do you do? You do not put in the high grade synthetic. Any good mechanic will have you add pure petroleum, commonly sold as Lucas, to the oil instead.
Yes, all natural petroleum. You use 100% real petroleum. The stuff our old engines were designed to run on. Is it cheap? No. Is it quick and easy? No. Does it always work the best? No. But it will make your engine last, and have good health.
My engine boring analogy has a point. Your body does treat any calorie as a calorie. But depending on all of the moving parts, it may prefer other calories. It may not run as well on a specific type of calorie. Just like an engine, no two people are exactly the same because no matter what, our engines wear differently and have different needs over time.
Just like a mechanic will diagnose your car, a dietician will try to diagnose your diet. No one is always right. We may have a neat trick which tends to work. But we can’t change the fact that there are variables. Calories in vs calories out is a bit simple for my liking because there are so many moving parts. But the truth is no one knows everything about our metabolism and how it all functions.
Why Do Our Bodies Prefer Different Types of Calories?
Woo! Loaded question time. My favorite part of writing for this website. I can’t help but hit my head against the wall when trying to explain this subject. This is why I strongly dislike anyone giving advice. You can’t have a strong stance on this topic because neither opinion is correct. It is true, a calorie is a calorie. It is also true, that a calorie is not a calorie. This as a concept makes no sense. Hopefully some of the reasons why will help.
Your engine (Your metabolism for those who spaced out for my bad analogy) does have preferences. It does not treat everything the same. This means your engine may burn a base amount of oil (Calories) but depending on which calories you fill it will, the performance can change. The best example of all calories not being created equal is when we look at sugar.
Yes, simple sugar.
Your have two common forms of sugar. Fructose and Glucose. They have the same chemical profile. They have the same caloric density. They look exactly the same. But to your body, they are complete different. Your entire body is designed to process glucose. Only your liver is designed to process fructose. Remember the article on body recomposition? All those pesky hormones? This is the clear example of where they come into play.
Fructose has some nasty hormonal side effects. Fructose raises Ghrelin, reduces satiety, and causes insulin resistance. You know what that means? You are more hungry, your body does not respond as well to carbohydrates, and stops your body from telling you to stop eating. This is just one example.
The next big example is the thermic effect of food. Every different macronutrient (Fat, carbs and protein) has a different thermic effect. This means your body requires a different amount of calories to burn each type of nutrient. Now, the science is not clear on the amount of thermic effect (So do not listen to anyone who says other wise) but in general, we know fat has the lowest thermic effect, carbohydrates are quite a bit more themic, and protein blow both out the water. By blow out the water, I mean ten times more calories required to consume protein over fat.
Protein also makes you feel more full and has a plethora of metabolic advantages. But not even all proteins are created equally. Plant protein and meat protein also have different effects on insulin levels and satiety, plus different thermic effects.
I am Still Confused.
The long and short of it is, everything you eat impacts your bodies metabolism. Why do our bodies do this? Biology. Biology is tricky. That is the honest truth, and outside the scope of this article. In fact, going any deeper normally includes weird theory of physics and the application of physics to biology. We attempt to explain what our bodies do with physics when we can’t get to the bottom of it with biology.
There is a reason when your thyroid is under preforming you go see an Endocrinologist and not a Dietician. Yes, the dietician can help you lose weight. But your weight change is a side effect of the thyroid function. When we get deep into the ‘science’ of calories in vs calories out, you get a lot of very educated opinions which are right and wrong. Everyone is looking at the ‘problem’ from a very specific perspective.
This is where I break things down where you should understand everything more clearly. This is what I call the dieting truth and weight loss truth. Are you ready for it?
“A Calorie is a Calorie.”
This is the answer. Sure, science proves that on average a low carb or keto diet is proven to help people lose more weight than any other diet type. The caveat is there are exceptions. Sure, protein is proven to burn more calories for digestion than fat, but some people still can’t lose weight on a very high protein diet.
We also have the common notion that Fat will make you fat. This is interesting because this was big for a while. By the thermic effect it all makes sense. The problem is we now know that cutting out carbohydrates helps you lose more weight. This is just an example of the confusion from having so many experts, and so few people trying to just agree we can all be right, and move on.
If you do not burn enough calories, you will gain weight. The question is not if a calorie is a calorie, it is. We get too caught up on that fact. The real question is are all nutrients the same. The answer to that is no. Fat is not fat. No all carbs are equal. Protein is not the same fat. Eating too much of anything will force you to gain weight. In general, some diets, or diets high in specific macronutrients are superior to weight loss. But at the end of the day, you can get fat on carrots or ice cream.
When it comes to your weight loss, you do not need to be a biologist, a dietician, a physicist and a endocrinologist. If you could even become all of that, it is no guarantee you will lose weight and be in shape. Body builders, models, and fitness experts are not all rocket scientists, and for good reason. If you treat a calorie as a calorie and try to burn more than you consume, weight loss is easy. Weight loss is only hard if you make it hard.
Find all the resources used in this article and the scientific basis of all our article at The Science Behind Fitness.