Before going deeper into nutrients and their other areas of importance, I first want to focus on the main purpose of why we eat: to obtain enough energy. In this text I will explain the basic mechanisms about how we make use of our food and the principles of our energy household and balance.
The information in this article may equip you with the tools to start counting your calories, but I do not recommend doing that at all. If you want to work on a healthy lifestyle, I tell you this is not the way. The goal is to understand the basic concepts of energy and how our body handles it.
Energy is what keeps us alive. Without energy, our internal processes would come to a halt, and we decompose to dead inorganic matter. Energy allows us to breathe, see, smell, hear, talk, walk, think and more.
The form of energy our body mainly uses is a small Molecule called ATP - Adenosine triphosphate. It gets produced by the so-called mitochondria, that lives within each cell of the body. ATP there gets recharged using the energy provided by carbs, protein, fat and alcohol.
ATP
ATP or Adenosine triphosphate is like a little thingy that can hold 3 phosphates. When phosphate is removed, energy gets released and the molecule then becomes a diphosphate or monophosphate.
In order to recharge it back to an energy rich ATP molecule, energy from our food gets consumed. During the day our body recycles more ATP than our entire body weights.
ATP is consumed in almost any process in our body. It is used to control neural signals, fire up chemical processes, to think and physical activity, but most of its energy goes into body heat. Whenever a molecule releases its energy, only a part of it can actively be used. 80% are radiated in form of heat.
If you ever wondered - Yes, that's the reason why your body heats up during activity, stress or illness. If your energy burn goes up, your body heat will follow.
How energy from food is used in our body
The energy we consume is not directly usable by our body. It first needs to be broken down in order to recharge ATP. The nutrients we can absorb energy from are carbs, protein, fat and alcohol. Each nutrient carries a specific amount of calories.
- Fat: 9 kcal /g
- Alcohol: 7 kcal /g
- Protein: 4 kcal /g
- Carbs: 4 kcal /g
When food arrives, energy first gets transported to where needed at the moment. The rest of the energy provided from our meal then gets stored. Before it lands in our body fat, first our "fast" storage gets filled.
Both the liver and our muscles are capable of storing energy. While the storage capacities of liver and muscles are limited (the muscle capacity can be expanded though), they are capable of a quick and controlled release of stored energy when needed. Extra calories exceeding these capacities get stored into your body fat. A storage distribution of energy can more or less look like this in a person of 70 Kilos of body weight.
Type of energy in kcal | |||
---|---|---|---|
Storage | glucose (carbs) | fat | protein |
Liver | 400 | 450 | 400 |
Body fat | 0 | 135 000 | 0 |
Muscles | 1200 | 350 | 24 000 |
How we use energy
The big chunk of energy we burn on a daily base usually does not get used for activity. We constantly need energy just to function. Our body needs in order to keep its temperature, breathe, circulate blood, think and grow its cells. The amount of energy we burn this way is measured as the basal metabolic rate. There are many ways of estimating the base rate, both through complex formulas and simple estimates.
As rule of thumb you can follow this easy calculation:
- Bodyweight in KG x 22 for Women
- Bodyweight in KG x 24 for Men
If you rarely move during the day, the basal metabolism can mark easily 70% of your total calorie burn. A more active lifestyle or job allows you to burn more calories in total. Multiply your base rate with a factor in between 1.2 and 2, depending on your activity level from low to high, you get a rough estimate for what your total calorie burn is. It is however an estimate and cannot replace a proper lab analysis.
Energy consumption and sport
Depending on your type of activity, the body swaps between several burning modes. For very quick intense exercise like pull ups or a sprint, we use up stored ATP directly. When used, this source of energy is finished in a few seconds and your muscle feels tired and cannot be used under the same stress level after the storage is depleted.
Your body then reacts to the local deficit. It releases ATP from other parts of your body and sends it to the area where needed. In only a few minutes your energy is back and you can repeat the exercise.
For activities less intense and demanding, your body does not touch the ATP reserves. It fills the need by producing new ATP on the fly from either glucose or fat. Glucose, or carbs, can release the energy around twice as fast as fats, while fats are more energy dense and provide you fuel over longer periods of time. Carbs therefore are burnt exclusively when energy is needed fast (anaerobic), while on lower activity levels the body burns a combination of fats and carbs. Via training it is possible to leverage the storing and access capabilities for each type of supply to a certain degree.
Energy and body weight
No matter the goal, a majority of people seem to be concerned about their body weight. While athletes try to hit their calorie goal in order to not lose valuable muscle, others might want to get rid of body fat with the goal of dropping weight.

Even though it is possible to influence what type of energy source is preferably used in exercise, the actual calorie balance at the end of the day is what matters. If you gain more energy than you burn during a period of time, you will build up body fat. If you keep on burning more than you consume, your overall body fat goes down.
However, it is not that easy, since this rule also knows its limits. In the end, the body still runs on the genetic code of survival of our ancestors. Just because we had the industrial revolution and get fed easily, this does not mean we are not functioning like in the age when getting our nutrients was our main concern.
To be energy efficient meant a better chance to survive. Muscle that we don't use actively, therefore consumes too much. If we don't move we will lose this tissue again in order to become more economical: Like this, the food we can find helps us to survive longer.
The same happens if you cut your calories too low. Your genetic survival instinct detects this bottleneck and will make sure to cut the calories burnt wherever possible. As a reward you risk losing muscle and lower your overall metabolism. Consequently, your initial reduction of the calories gets overtaken by your metabolism and pile up body fat on your hips again.
Energy and weight loss in a healthy manner
To lose weight, your caloric intake should be lower than your calories burned. Remember this as the basic rule. However, you also want to avoid triggering your survival instinct in order to save the energy again.
Ideally try not to undercut 15% of your daily need. If you do, this can slow down your metabolism and sacrifice muscle instead of fat. Considering that one gram of fat has 9 calories, you should be aware that rapid weight loss is not possible without sacrificing your health. 15% of 2000 calories make only 300 kcal. That's roughly a Croissant or a medium-sized Snickers. The good news is: that one Snickers can make a difference already.
Calculate your calories and weight change potential
Basal metabolic rate
daily calories burnt
Your calorie difference:
Your daily body fat change:
Your calorie intake should not lower than 15% of your daily energy need (you are at %)
When taking those 15% as a hard limit based on a daily energy need of 2000 kcal, your lower limit for calories should be around 1700 kcal. With the 300 calories saved you burn 33g of body fat daily. That's roughly one kilo of body fat per month or 230g per week.
Why so many diets are shit
Many diet plans promise rapid weight loss and play with temptation. 5 kilos in just 2 weeks? Hell yes - this sounds too good to be true. But does it sum up?
Even if you ate nothing at all - with 2000 kcal burned you would roughly lose 222g of body fat per day or 3.1 Kilos in 2 weeks. That's still 2 kilos below the promised result.
When encountering a super promising diet plan, you should be able to see through and find how big of a lie and danger this promise can be. Being sceptical is the most healthy thing you can do when checking your options.
Even if it is clear that the goals cannot be archived as advertised, you might still tap into the trap and lose muscle instead of body fat. On top of that, a massive cut of energy usually comes with a massive cut of other nutrients.
Your diet then literally makes you sick, if you expose yourself to a deficit over a too long time. It can lead into a state of weakness, tiredness and lack of concentration. Longer lasting deficits also cause permanent damages to your nerves, organs and brain.

So what if you do a month of diet in order to reduce body weight? Sure, you might see good progress in the beginning. That is often explained by loss of water and the drop of previously high amounts of food in your guts.
After a couple of days, the speed of weight loss then usually slows down rapidly and follows the maths explained above. You most likely will also lower your metabolism and lose muscle. Once your metabolism is adapted to your calorie intake, you will encounter weight gain again. This is well known under the term yo-yo effect.
When not interpreted correctly, this might lead you to taking the diet even more seriously and you start the circle again. You start treating yourself more strictly in order to underbid your metabolism again. The vicious circle becomes tighter and tighter, while your supply of nutrients gets poorer and poorer.
What happens if your diet ends?
Okay… Let's assume you pull off a program and follow a diet and lose weight in a controlled and healthy manner. At some point you reach your goal. And now what?
If you happily reach your goal, you might want to return to "normal". This normal however is responsible for the body weight as it was before the diet. If you then continue as before, your body weight again will slowly climb up.
Making a diet as a "one shot" out of the sudden appears pretty pointless. All this self-torture on the long run only causes you harm and leaves you even more frustrated once you realize you are back on your way to where you came from.
Healthy weight loss therefore is something slow and permanent. It is a change in your overall lifestyle. It is not a "program", that you can run and become a different person, like when you obtain a certificate that allows you to bear this and that title. No it is not. If you want to archive something permanent, you need to change your habits permanently.
The only proper way of losing weight
I think you got it by now. In order to lose weight, you need to change your habits. You should not fall for any high numbers being promised to you and you should accept that change in body weight and stature is a slow process bound to a permanent change of habits. But how do you start it?
The proper way of getting started is by knowing where you are. If you watch your body weight over a couple of weeks while not going through any diet change and you see your body weight stays stable, your average dietary intake most likely hits your body's current demand. If weight is slowly and steadily climbing, you eat too much.
If you want precise numbers, you can make a lab test. By measuring the levels of carbon dioxide in your breath while looking at your physical stress, it is possible to exactly mark your metabolic rate in both rest and activity.
Keep in mind that you have 3 touch points on which you can change your caloric balance: your base metabolism, your intake and extra exercise. You either raise the bar of what you need, or you lower your intake below the current bar.
Focusing only on one of those pillars can feel extreme and require a lot of effort and self-control. Since we are counting calories on both sides of the balance, you can get the same overall effect by slightly shifting each one of these 3 factors.

Practically, this can mean to be just some more active than before, while changing parts of your diet. Ever fancied to try out that yoga class? Dreaming of learning to dance? Go for it now! It does make a difference. At the same time, make a little change in what you eat. Cross out that sweet treat, change your calorie packed dinner for something less processed and more nutritional.
If you manage to raise your base metabolism through a more healthy and active lifestyle, your calorie gap even rises from what you initially started with. Things then might slowly speed up for you. Just make sure to not open the gap too far, in order to not let the survival mechanism kick in again. Keep things balanced.
Its the mindset what matters
Stating to walk down this long road might appear frightening. You probably are concerned about the cuts you have to make, fear to miss out social occasions and picture change as an everlasting self-punishment. All those things that you HAVE to do or change, in order to archive one single goal, can easily end up in a severe state of frustration.
All those things you have to drop and sacrifice, in order to become that better version of you, feel like an unbeatable challenge and a loss. You might drop confidence even before you starting the change, which makes the first steps even harder. Combined with the experience of previous approaches, this might lead you into not even getting started.
This all can be different, if you start changing your perspective. Take that ideal version of yourself, who might be your ultimate goal to be like. If you constantly ask yourself what you HAVE to change and improve on, in order to BECOME this way, you are constantly facing situations that tell you how wrong, weak and impersistent the current version of you is. Instead, just start BEING your better self.
Your better self has good habits, so you can have them too. Start of with the right confidence by seeing the world through the eyes of what you aim for. Think the way, act the way, be the way. Experience right from the start how well your better self feels, by living this good lifestyle. Don't change in order to become. Be in order to experience the change.
When you just start living by your ideal with confidence, the change will happen as a side effect. Don't focus on the cut you make to move away from your old self. Focus on how being the better self brings you a good feeling. Feeling superior over your old self automatically leads to improvement.
Being the good you becomes routine over time. And with routine the good you already is the normal you. From here, things out of the sudden are not even worth a sweat or thought. It then again is normal to be how you are.
In the end it is not about counting calories
To live healthy, you should ultimately not start counting calories. This is the best approach to start stressing yourself before you even get going. Living healthy means to sleep well, be active, drink enough and eat well. And the good news is: all of this also impacts your metabolism. Besides that - every person has its own individual metabolism. There is no single formula to cover all.
It is not about cutting and restricting. It is about change. Swap this processed junk food and replace it with something fresh and nutritious. Start cooking. And if you can't, then learn. The internet is full of easy to follow recipes. When you eat healthy, then you can eat much of it as well.
For a healthy lifestyle, you must look at more than just nutrition. Sleep and exercise go hand in hand with it to produce your personal feel good vibe. If you unlock them together, you start blooming in no time.
In a nutshell
You need energy in order to survive. Our bodies run on the instinct of our ancestors and is configured to be as energy efficient as possible. Carbs and protein deliver 4, alcohol 7 and fat 9 kcal per gram.
Healthy weight change is a slow and steady process and you should not undercut your caloric needs by more than 15%. A balanced approach in weight loss is a combination of activity and diet change.
A long-lasting change in body can only be archived by a change of your habits. A diet or sport program as a one shot often fires back and can leave you where you started off after a while. In the end a healthy lifestyle is more than just counting calories, but an overall improvement of your habits.