What are carbohydrates? Clarity about carbs

As an important source of energy, carbohydrates are a central component of a balanced diet. Depending on their structure, a distinction is made between monosaccharides, disaccharides and polysaccharides. Everything else you need to know about carbs can be found in the article.

What are carbohydrates

When you think of carbohydrates, you might immediately think of pasta, rice, cakes and the like. You're not wrong - because these foods are rich in the often demonised carbs. But that's not the whole story. Carbohydrates are one of the three macronutrients contained in most foods in varying proportions and forms. And that's a good thing - after all, they are an important source of energy for our body and the only fuel for brain and nerve cells. Carbohydrates (also known as saccharides in technical jargon) are therefore much more than just something you eat as a side dish or dessert. You can find out what carbs can do, where you can find them and everything else you need to know about carbohydrates in this article.

How are carbohydrates formed?

Carbohydrates in their simplest form (= simple sugars) are formed by plants during photosynthesis. Simple sugars are formed from carbon dioxide (CO2) from the air and water from the soil with the help of chlorophyll in the plant's leaves and sunlight. From these monosaccharides, plants subsequently form polysaccharides and polysaccharides, which serve as food for humans and animals.

Are all carbohydrates the same?

Yes and no. In their basic substance, all carbohydrates consist of carbon and water. However, depending on how many simple sugar molecules are combined to form a compound, they differ in properties and flavour.1

What types of carbohydrates are there?

Simple, double, multiple, short-chain, long-chain, complex, digestible, indigestible...? The terms used to describe the different types of carbohydrate are often more complicated than the nutrient itself. We bring clarity to the carbohydrate jungle. Because the truth is that the variety of types is limited and there are only three genera: Monosaccharides, disaccharides and polysaccharides.

Simple sugars (monosaccharides)

As the name suggests, monosaccharides are the simplest form of carbohydrate. They consist of just one sugar molecule. The best-known representatives of the monosaccharide genus are glucose (grape sugar) and fructose (fruit sugar). They occur in their natural form mainly in fruit and honey, but also in some vegetables and have a very sweet flavour. Simple sugars are water-soluble and easily digested. This is why they are quickly absorbed into the bloodstream and provide energy quickly.1 For this reason, they are often referred to as "fast carbohydrates".

Disaccharides

Disaccharides are formed by the combination of two simple sugar molecules. They are also known as double sugars or short-chain carbohydrates. The best-known forms are sucrose (cane or beet sugar; also known as table sugar) and lactose (milk sugar).2 During digestion, disaccharides are first broken down into monosaccharides before they are made available as an energy source. They are therefore absorbed into the blood somewhat more slowly and do not cause blood sugar levels to rise quite as quickly as simple sugars.

Multiple sugars (polysaccharides)

Multiple sugars consist of a large number of simple sugar molecules. If there are three to ten, they are also referred to as oligosaccharides or polysaccharides. Compounds consisting of more than ten simple sugar molecules are called polysaccharides.

And what are long-chain carbohydrates? They are also polysaccharides. Due to their chemical composition, they are also known as high molecular weight or complex carbohydrates. And polysaccharides are certainly complex. This is because polysaccharides can either be directly utilised or not directly utilised. In other words, they are broken down in the digestive tract by enzymes (= directly usable, e.g. starch in potatoes, cereals or pulses) or excreted undigested (= not directly usable, e.g. cellulose contained in fruit, vegetables and whole grains). Non-utilisable polysaccharides are also known as dietary fibres, which provide a lasting feeling of satiety and contribute to healthy digestion. Keyword digestion: multiple sugars need time. This is why they also provide long-term, consistent energy and stabilise blood sugar levels.3

Carbohydrate table: The different types of carbohydrates at a glance

Designation: Simple sugars

"Nicknames": Monosaccharides, simple carbohydrates, fast carbohydrates

Most important representatives: Glucose (dextrose), fructose (fruit sugar)

Naturally occurring: Fruit, vegetables, honey

Are carbohydrates good or bad?

There is no generalised answer to this question. As explained above, carbohydrates differ in terms of their structure and properties. Different types of carbohydrates are better or worse at certain times depending on your physical composition and activity as well as your individual goals. But above all they are one thing: necessary. Carbs are friends and an essential part of a balanced diet.

Carbohydrates in the body

Carbohydrates, together with protein and fat, form the infernal trio of macronutrients. These are the nutrients that supply our body with energy and are necessary for the maintenance, development and smooth functioning of all bodily functions. Carbohydrates perform particularly important tasks.

What functions do carbohydrates fulfil in our body?

The main task of carbohydrates is to supply our body with energy. For some cells, saccharides (more precisely the simple sugar glucose) are even the only usable source of energy: a sufficient supply of carbohydrates is essential for brain and nerve cells, kidney marrow and red blood cells. They also serve as building materials for our connective tissue and cell membranes.

Indigestible polysaccharides (dietary fibres) are of particular importance. They stimulate our chewing activity and digestion, ensure a lasting feeling of satiety, are involved in the binding of bile acids and thus the regulation of cholesterol levels and ensure slow carbohydrate absorption into the blood. This balances our blood sugar levels, which leads to a constant energy level and long-term physical and mental performance.

Carbohydrates not only provide immediate energy, but can also be converted into storage. In the short term, they are stored in muscles and the liver in the form of glycogen. If the glycogen stores are full and we consume too many carbohydrates over a long period of time, these are converted into fat deposits for long-term storage of energy reserves.4 But how many carbohydrates are too many?

How many carbohydrates per day do I need? (Carbohydrate calculator)

How many carbohydrates you need per day depends on your general energy requirements. This in turn is made up of various factors, such as height, weight, age, gender and activity level. It is generally recommended that over 50% of the daily energy requirement should be covered by carbohydrates.4 With a daily requirement of 2,200 kcal, this means that over 1,100 kcal should be consumed through carbohydrates. This corresponds to around 270 g. This calculator gives you an estimate of how much carbohydrate you should consume per day based on your individual body composition. For an exact calculation, however, you should determine your individual energy requirements. We explain how this works step by step in our article on fat burning.

Do carbohydrates make you fat?

In short: No. A long-term surplus of energy (= calories) causes us to gain weight, not a single nutrient. This means that if you eat more calories than you consume over a long period of time, your weight will increase. It's not the carbohydrates that are to blame, but an excess of energy.

Carbohydrate calories - what you need to know

Have you ever wondered how many calories carbohydrates contain? It's not as many as you might think: Burning one gram of carbohydrates provides 17 kJ (that's 4.1 kcal). This means that carbs provide the same amount of energy per gram as protein and far less than fat (9.3 kcal).5 Carbohydrates - especially in complex form - are an important source of energy and an essential part of a balanced diet.

Carbohydrates on the menu

Here we explain everything you need to know about healthy carbohydrates in your everyday life.

Which carbohydrates should I eat?

You should consume two thirds of the carbohydrates you need every day in the form of polysaccharides. You can find these in wholemeal products, potatoes, vegetables and pulses, for example. The remaining third can be supplied by single or double sugars from fruit and sweets. It is also recommended to cover a maximum of 10% of your daily energy requirements with industrial sugar and to consume at least 30 g of fibre per day.6 Fibre is mainly found in wholegrain products, fruit, vegetables and pulses.

Which carbohydrates are contained in which foods

Where are there lots of carbohydrates, where are good carbohydrates and are there also foods without carbohydrates? You can find an overview of the most important foods in our carbohydrate list, that provide you with carbs

Carbohydrate food overview

Rich in healthy carbohydrates (polysaccharides and fibre)
  • Wholemeal products
  • Vegetables
  • Pulses
  • Fruit

You should cover at least ⅔ of your daily carbohydrate requirement with these products.

Rich in fast carbohydrates (monosaccharides and disaccharides)
  • Fruit (esp.
  • Milk and dairy products
  • Honey

You should cover a maximum of ⅓ of your daily carbohydrate requirement with these products.

Rich in industrial sugar
  • Sweets
  • Pastries
  • Soft drinks
  • Ready meals and junk food

You should cover a maximum of 10% of your daily carbohydrate requirement with these products.

When should I eat carbohydrates?

This depends very much on your goals. If you want to maintain or gain weight, you should make all your meals as balanced as possible. This means: at least 50% carbohydrates, approx. 30% fat and 10-20% protein7 If you want to lose weight or reduce body fat, it can be useful to reduce the "carbohydrate window". You can do this by avoiding carbohydrates either in the morning or in the evening. This empties the carbohydrate stores in your body and you burn fat if you are in a calorie deficit.

Carbohydrates and sport (training)

Here we explain the most important facts about the interplay between carbohydrates, sport, regeneration and muscle building.

Carbohydrates before training

Eating fast carbohydrates (= simple or double sugars, e.g. in the form of fruit) shortly before training gives you quickly available energy. However, this is also quickly used up again. Before longer training sessions, we recommend complex carbohydrates, which are stored as glycogen in your muscles and then used as a source of energy. Eating a carbohydrate-rich meal (such as pasta, rice or potatoes) 1.5-2 hours before exercise provides you with optimal power for prolonged or intensive training.8

Carbohydrates after training

Immediately after training, your muscles start their regeneration. This primarily means that the glycogen stores are replenished. What do we need for this? That's right, carbohydrates - and in a form that is available as quickly as possible. Monosaccharides and disaccharides are therefore the ideal post-workout snack. To speed up their absorption, you can also consume them in liquid form, for example as a smoothie or shake.9

Carbohydrates for muscle building

Protein is often cited as the most important macro-nutrient in connection with muscle building. This is justified, but it is by no means the whole story. In order to build muscle, all of the following three factors are necessary:

Positive energy balance + strength training

The basic prerequisite for building muscle is a positive energy balance. This means that you need to consume more calories than you burn. The excess energy is then converted into muscle when combined with strength training. Carbohydrates are important suppliers of this necessary energy.

Sufficient supply of protein

Yes, the highly praised protein plays a central role in muscle building. This is because the amino acids contained in protein are the most important building blocks of our body cells10 However, they alone are not enough to build muscle.

Adequate supply of carbohydrates

Carbs are friends! This is especially true when it comes to building muscle. They are not only an important source of energy, but also provide the glucose that is essential for building and regeneration. In addition, the insulin released during the digestion of carbohydrates is the most important anabolic (= muscle-building) hormone. This substance is what makes the transport of protein into the cells and the resulting muscle building possible in the first place.11

What does my body use as fuel when I eat too few carbohydrates?

With a balanced calorie intake, your body draws its energy from the food you eat. In addition to carbohydrates, proteins and fats provide energy. So if you reduce the amount of carbohydrates in your diet but continue to eat the same number of calories, you will replace the energy from carbohydrates with protein and/or fat. These then serve as fuel for your body.

The situation is slightly different with a calorie deficit. If you consume less energy from food than you burn, your body will draw on its stored energy reserves. In the short term, these are the glycogen stores in your muscles and liver. Once these are used up, the body begins to burn the long-term stores (= fatty tissue) to generate energy.12

Conclusion

Carbohydrates are an essential part of a balanced diet. They fulfil important functions in the body and are the only source of energy for the brain and nerve cells. Carbohydrates are divided into three groups according to their chemical structure: Monosaccharides, disaccharides and polysaccharides. Monosaccharides and disaccharides provide quick energy, while polysaccharides ensure longer satiety and a stable blood sugar level.

Frequently asked questions

What contains the most carbohydrates?

Starchy foods such as cereal products (bread, pasta, rice), potatoes and pulses contain the most carbohydrates. High-sugar foods such as fruit, juices, honey and confectionery are also high in carbohydrates. Hidden carbohydrates can also be found in many processed products such as ready meals, sauces, dressings and soft drinks.

Which carbohydrates should you not eat?

You should avoid highly processed and high-sugar foods with readily available carbohydrates, as they cause blood sugar levels to rise rapidly and can favour obesity and health problems in the long term. These include products such as white flour, sweets, snacks, cakes, sweetened drinks, breakfast cereals and cornflakes. Ready-made products and fast food are also often high in unfavourable carbohydrates.

What are all healthy carbohydrates?

Healthy carbohydrates are primarily complex carbohydrates that are broken down and utilised more slowly in the body. They are found in all natural, preferably unprocessed plant-based foods: Wholemeal cereals and products, pulses, vegetables, fruit and pseudo-cereals such as quinoa or amaranth. Milk and dairy products also contain the healthy milk sugar lactose.

Sources
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