Table of contents
1 Reducing body fat: why actually?
2 Body fat: what is it actually?
3 Body fat percentage: how to calculate or measure it?
4 Weight loss vs. fat reduction: what's the difference?
5 Fat metabolism: how fat burning works
6 Calorie deficit: the be-all and end-all of losing weight
Calorie requirement - how much energy do I need? Energy balance Setting goals - what is realistic? Tracking calories - what's the easiest way?
7 Nutrition tips: what and when is the best time to eat?
8 Exercise and fat burning: what is most effective?
9 Lifestyle: what you should pay attention to
10 The 7 steps to less body fat

How to lose weight in the long term, healthily and without the yo-yo effect, why you should avoid sugar and alcohol and what stress has to do with your weight: We answer your questions about burning fat.

In this guide, we explain the basics of fat burning, the difference between body fat and weight loss and how you can overcome various challenges when losing weight. Most diets make it more complicated than necessary and are also difficult to maintain. In this article, we explain the most effective method for long-term and healthy weight loss: a gradual reduction in body fat.

Reducing body fat: why actually?

A healthy body fat percentage is not only reflected in the mirror. Our health will also thank us if we reduce excess fat. A normal weight and ideal body fat percentage promotes our vitality, energy and zest for life. Being healthy and fit simply feels good and is not as difficult as we often think.

Being overweight and obese comes with a variety of risks: cardiovascular disease, diabetes and joint problems are just the tip of the iceberg.1 A myriad of related symptoms are caused by excess stored fat and negatively affect both physical and mental well-being.

Body fat: what is it actually?

Alongside water, bone and muscle mass, fat is a central component of our body. To a healthy extent, body fat is vital and fulfills important functions. First and foremost, it is responsible for protecting our organs, being available as a building block for cells, storing energy and keeping our hormone and heat balance in equilibrium.1 A healthy body fat percentage is between 19 and 25 % for women and between 13 and 18 % for men.3

Body fat percentage: how to calculate or measure it?

You can find out whether your body fat percentage is within this ideal range with tools like this. To do this, you need the measurements of your hips, waist and neck, your body weight and your height.

In addition to this simple calculation, there are also various measurement methods to determine your body fat percentage. Although these are a little more complex, they provide more accurate results. The caliper, for example, measures the fat values at various points, such as the lower abdomen, triceps or thighs, and provides information about the fat index in the body by calculating the weight and fold size.You can find a detailed explanation of this method here.

Other methods for measuring body fat percentage are summarized under the term "bioelectrical impedance analysis". In this measurement technique, your body fat percentage is calculated based on the specific conductivity of different types of tissue. This is measured using metal electrodes, which can either be built into scales or placed on the hands and feet in the form of small tongs.4

Weight loss vs. fat reduction: what's the difference?

Colloquially, people often talk about "losing weight" or "reducing weight" in connection with health and nutrition. However, these phrases are very misleading. This is because the number on the scales is a poor indicator of our state of health and fitness. Body composition is much more important than weight. This is primarily about the ratio of body fat to muscle mass.

"Losing weight" in the classic sense means nothing other than reducing your overall body weight. However, this also happens if you eat or drink less for a while. However, it is not the food in your digestive tract or the water in your cells that is responsible for excess and disease-causing kilos. Weight loss in this form therefore does not have the desired effect and does not last.

Extreme diets that involve a very high calorie deficit in the long term are also not recommended. Although you can sometimes lose a lot of weight in a short period of time, this is mainly in the form of muscle mass[5, 6]. It takes more energy to maintain muscle than fat cells. As an "economy measure", the body therefore breaks down the muscles first if there is a shortage in order to generate energy for vital processes.7 However, the fatty tissue that surrounds muscles and organs and makes up the excess kilos remains. This makes you lighter, but not healthier. It also usually doesn't bring you any closer to your goals visually.

So it's not primarily about losing weight, but about reducing your body fat percentage. And, if possible, without losing muscle. This will gradually change your body composition and your figure. This may take longer than the next crash diet, but it is much more sustainable.

In this context, it is also important to remember that muscle mass is denser than fat mass. This means that 1 kg of muscle mass has less volume than 1 kg of fat.8 Depending on your starting position, you may not lose weight or even gain weight by reducing fat and building muscle. However, your body shape and clothing size will still change. And for most people, this is what they really want.

Fat metabolism: how fat burning works

Stored body fat is only broken down (i.e. broken down by digestive enzymes and released as energy) when the body is in a calorie deficit. This means that fewer calories are supplied than are consumed. In principle, fat is designed as a long-term energy reserve and is therefore only attacked after the glycogen stores in the muscles and liver have been emptied. Glycogen is the short-term energy store derived from carbohydrates.9 This is also the reason why a low-carb diet is considered beneficial for fat burning. If you consume fewer carbohydrates, your glycogen stores are depleted more quickly and your body draws on fat stores for energy. At least in theory. This theory is now scientifically disputed.10 According to the latest findings, the central factor for burning fat is not the relationship between the individual macronutrients. More important is the calorie balance, i.e. the ratio between calories consumed and calories consumed. Fat is only burned if this balance is negative, i.e. if you consume less energy than you burn. This is also referred to as a calorie deficit.11

Calorie deficit: the be-all and end-all of losing weight

Calorie requirement - how much energy do I need?

The World Health Organization (WHO) gives 2,000 kcal for women and 2,500 kcal for men as a guideline for daily calorie requirements.12 However, individual energy requirements depend on a variety of factors such as age, physical activity and body composition. We therefore recommend that you calculate your exact calorie requirements yourself.

However, you do not have to carry out these calculations yourself. Our calorie calculator helps you to calculate your daily energy requirements based on your age, gender, height, weight and activity level.

The most common method is the Harris-Benedict formula. With this formula, you can first calculate your basal metabolic rate. This is the energy requirement that is necessary to carry out vital bodily functions at absolute rest and 28 degrees Celsius. It is therefore the absolute minimum amount of calories that you should consume daily through food and that you should never fall below, even when dieting. The basal metabolic rate can be calculated using the following formulas:

Women: 655.1 + (9.56 × weight in kg) + (1.85 × height in cm) - (4.7 × age in years)
Men: 66.5 + (13.75 × weight in kg) + (5.0 × height in cm) - (6.76 × age in years)13

Factor Activity Example
0.95 Sleep -
1.2 only sitting or lying down frail people
1.4-1.5 sitting, hardly any physical activity Office work at a desk
1.6-1.7 Mainly sitting, walking and standing Students, pupils, cab drivers
1.8-1.9 Mainly standing and walking Salesperson, waiter, craftsman
2.0-2.4 physically strenuous work Farmers, top athletes

Table 1: PAL values and activities14

You then multiply the factors by the number of hours you spend on each activity. The results are then added together and divided by 24. This gives you your average PAL value per day. You then multiply this by the previously calculated basal metabolic rate to obtain your total metabolic rate, i.e. your total daily calorie requirement.

For an even more detailed calculation, you can have a sports science measurement carried out by a doctor or trainer. In addition to the factors mentioned above, your body composition and the different energy consumption of fat and muscle tissue will also be taken into account.

Energy balance

The basic prerequisite for burning fat is a negative energy balance. This means that you must consume fewer calories than you burn. This puts you in a so-called calorie deficit and the body's fat stores are gradually used as energy sources and burned.

Large calorie deficits are not recommended in the long term, as they can lead to a lack of energy, fatigue and cravings. With a chronic calorie deficit, our body switches to "survival mode" and only carries out the most necessary processes. Concentration and performance can suffer greatly as a result.15 The yo-yo effect is also inevitable with an excessive calorie deficit: as soon as you start to consume more energy from food again, your body builds up as many fat deposits as possible in order to be prepared for future periods of hunger[15, 16].

Finding the optimal calorie deficit is a balancing act and varies from person to person. As a guideline, we recommend a deficit of 200-500 kcal per day in order to lose weight sustainably. The most important thing is that you can maintain the deficit in the long term without feeling hungry. This will help you avoid the undesirable side effects that many diets entail. Basically, the smaller the deficit, the easier it is to maintain it consistently. This means you lose weight more slowly, but the likelihood of a yo-yo effect is lower.18

For example, if you want to lose 5 kg, you need a total calorie deficit of 35,000 kcal.[19, 20] If you reduce your daily calorie intake by 200 kcal, you will reach your goal in 25 weeks. With a calorie deficit of 500 kcal per day, it only takes 10 weeks, but is much more difficult to maintain. The important thing is not primarily how quickly you lose weight and body fat, but how sustainably. Achieving the ideal body composition is not enough - you also have to be able to maintain it in the long term.

Setting goals - what is realistic?

It is therefore essential to set yourself realistic goals and make a concrete, achievable and measurable plan. With the recommended calorie deficit of 200-500 kcal, you can lose approx. 0.2-0.5 kg per week. That may seem a little low, but over a whole year that's 10.4-26 kg. So it's worth sticking with it.

By gradually and slowly reducing your weight, your body can adjust to the new situation and you will achieve long-term success with minimal effort. Keep your goal in mind and move towards it in small but steady steps. Support from outsiders can help enormously. This could be a reliable person from your circle of friends or a coach who constantly motivates you and holds you accountable if you are inclined to stray from the path.

It is also important to document your progress. Weighing yourself regularly and measuring your body fat percentage are the most common parameters. However, you can also record personal factors such as well-being, energy levels and body perception. Our tip: think about your motivations at the start and adapt your success measurement accordingly. In any case, you should keep a written record of your development so that you can monitor your progress over long periods of time.

Tracking calories - what's the easiest way to do it?

To keep an eye on your calorie deficit, you need to know your calorie intake as well as your daily energy requirements. The nutritional value tables on products are helpful here. The only important thing is to convert the information to the amount you actually eat.

If you cook yourself or combine different foods, add up the energy content of the individual ingredients.You can easily find the energy content of individual foods on the internet. You can then document and add up these figures either manually or digitally. Apps like Lifesum or Cronometer make calorie tracking easier and also have various dishes in their database, so you don't necessarily have to enter the individual ingredients. However, the calorie content of a dish naturally depends on the exact method of preparation. Therefore, the information in such apps is more of an estimate and does not necessarily reflect the actual energy content of your meals.

Tracking calories can seem very time-consuming at first. Over time, however, it becomes routine and becomes easier and easier. You also gradually develop a feeling for how many calories certain foods and products contain. As a result, the effort involved in calorie tracking becomes less and less.

Nutrition tips: what and when is the best time to eat?

The calorie content of food is not the only factor that influences fat burning. Quality and composition also play an important role.

Above all, you should avoid sugar, alcohol and ready-made products. These foods slow down the metabolism and lead to cravings and excessive calorie consumption[21, 22, 23].

However, there is no need to shy away from healthy fats, such as those found in nuts, avocados or fish. Dietary fat does not automatically lead to increased body fat. It's the calorie balance that counts. And as long as this is negative, high-quality fats are an essential part of a balanced diet.24

Plenty of fruit and vegetables and high-quality sources of protein should also be on your daily menu. The fiber contained in plant-based foods keeps you full and supports your digestion.25 Protein, on the other hand, is essential for building muscle. So if you want to lose fat and build muscle, we recommend a diet rich in fiber and protein.

You should also drink enough to avoid cravings and support your body in its natural detoxification processes. Ideal drinks to help burn fat are water and unsweetened teas (especially green tea).26

However, not only the "what" but also the "when" of your diet plays an important role in your body composition. Your digestion is usually at its strongest at lunchtime.27 You should therefore eat your main meal then if possible and eat less towards the evening so that your body can recover during the night. You should also eat as regularly as possible. This prevents cravings and prevents your body from going into the "survival mode" described above.

Intermittent fasting is also very popular in connection with fat burning. This involves planning your meals so that you have a daily "fasting window" of at least 16 hours in which you do not consume any calories. This is what a day of intermittent fasting can look like:

  • After getting up: Water, green tea, black coffee
  • 10 a.m.: Breakfast 
  • 2 p.m.: Lunch
  • 6 p.m.: Dinner
  • Evening: Water, unsweetened teas

This leaves 16 hours between dinner and breakfast the next day, during which your body can draw on its fat reserves for energy. Depending on your personal daily routine, you can set the "fasting window" to best suit your lifestyle.

Sport and fat burning: what is most effective?

Do you agree that cardio training is the only way to burn fat? If so, you're not alone. Nevertheless, this assumption is a myth. As already mentioned, fat burning is primarily about calorie balance. Therefore, the more calories you burn doing a sport, the more it contributes to burning fat.28 Strength sports also promote muscle building, which can have a positive effect on your body composition. In addition, sports that work your muscles lead to the so-called afterburn effect. This means that you continue to burn energy after training because the muscles regenerate and remain active.29

So you don't necessarily have to go running for an hour every day to burn fat. Every form of exercise consumes additional calories and therefore promotes fat burning.[30, 31] Different types of sport consume different amounts of energy. However, the exact values depend on several factors. Your age, height, weight, training status and heart rate are just a few examples of factors that influence your calorie consumption during exercise. For more precise information, we therefore recommend a fitness tracker that records your movements and heart rate and calculates how much energy you have burned based on your data. It also gives you an automatic overview of your workouts and your progress. After all, it's also important to set yourself realistic goals when exercising that you can stick to and document in the long term. A training buddy or coach can also support and motivate you here. Sport is simply more fun together. And if it's fun, you'll stick with it.

You can also bring more movement into your everyday life. Take the stairs instead of the elevator, get off the bus one stop earlier and walk a bit or take the bike to work every now and then. Small changes like these cost little and yet bring a lot.

Lifestyle: you should pay attention to this

Not only diet and exercise, but also rest and relaxation play an important role in burning fat. Sufficient and healthy sleep lays the foundation for an optimally functioning body.32 We are also less tempted to reach for junk food and sugar when we are rested33 You should get at least seven hours of sleep a night to keep your body healthy and efficient.34

You should also avoid stress as much as possible if you want to burn fat. Survival is your body's top priority and stress tells it that it is in danger. It therefore builds up energy reserves to protect itself and ensure its survival.35 Fat is only burned when your body feels calm and safe.

We also make poorer decisions when we are tense. This is especially true when it comes to our food choices. Pizza, ice cream and chocolate are suddenly much more tempting in a stressful situation. This is also due to the perceived danger. When we are stressed, our body, which is geared towards survival, searches for quickly available energy to be prepared for an escape or a fight in an emergency.[36, 37] Your body does not know that the deadline at work or a busy schedule are not an immediate threat to life. Consciously reducing and relieving stress should therefore be just as much a part of your fat-burning plan as a healthy diet and regular exercise. Breathing techniques or conscious forms of exercise such as yoga can help to bring more relaxation into your life and therefore burn fat more easily.

The 7 steps to less body fat

  1. Set yourself a concrete, long-term goal. What do you want to achieve and why?
  2. Calculate your total calorie requirement. Calorie calculator like this one will help you.
  3. Track your calories for a week. This will give you a feel for what your calorie balance looks like.
  4. Make a concrete plan. Determine your daily calorie deficit and your weekly training goal and write them down.
  5. Find a motivational buddy. Share your challenges and successes with someone who will support you and keep you accountable. 
  6. Measure your progress. Think about how you want to measure your success at the beginning and set up regular interim checks (e.g. fortnightly body fat measurements and weigh-ins). 
  7. Relax! Good things take time. Small, continuous steps will get you to your goal. Take time to get enough sleep and rest. Only a relaxed body is a healthy body.

Collapsible content


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