Macronutrients are the foundation of your diet
If you’re setting off on a long run, have an intense yoga session ahead of you, or simply want to get through your day with focus, your body needs energy. Lots of energy. But where does it get it from? And what actually happens to the things you eat?
The answer lies in the macronutrients – that is, carbohydrates, fats and proteins. They are the three key components of your diet that your body uses every day to function, recover and keep you performing at your best. And although everyone has heard of them, surprisingly little is known about how these nutrients actually work – and how you can make the most of them.
Carbohydrates – Sugar with a plan
Essentially, carbohydrates are nothing more than sugar – in various forms and chain lengths. In your body, they are broken down into glucose, a simple sugar that serves as fuel for every cell. The brain and muscles in particular love glucose because they can quickly draw energy from it.
However: Not all carbohydrates are the same. What matters is how quickly they enter the bloodstream – and what else comes with them. Here is a brief overview, set within the wider context:
- Simple sugars (e.g. glucose, fructose) cause blood sugar levels to rise rapidly. They provide a quick energy boost – but also lead to rapid energy crashes. Ideal for treating hypoglycaemia or during intense physical exertion.
- Complex carbohydrates (e.g. the starch found in potatoes or wholemeal products) are digested more slowly. They provide a steady supply of energy, keep you feeling full and have a more beneficial effect on blood sugar levels.
- Fibre is technically classified as a carbohydrate – but it is not digested. Instead, it keeps the gut working properly, promotes healthy gut bacteria and slows down the absorption of sugar.
The interplay between these forms determines your energy levels. It is therefore not just how many carbohydrates you eat that matters – but which ones.
Fats – More than just calories
Fats have long had a bad reputation. Unfairly so. They are essential – that is, vital – and play a central role in energy metabolism, particularly during periods of rest or during prolonged physical exertion. They are not only sources of energy, but also components of every cell membrane, carriers of fat-soluble vitamins (A, D, E, K) and important precursors for hormones.
The role of unsaturated fatty acids – particularly omega-3 fatty acids – is especially fascinating. They have anti-inflammatory effects, protect the heart and blood vessels, and even influence the function of nerve cells.
To help you get a better picture, here is a useful classification:
- Saturated fatty acids: Found mainly in animal products (butter, meat, cheese); they are considered harmless in moderation, but in excess they are a risk factor for cardiovascular disease.
- Monounsaturated fatty acids: Found in olive oil, avocados and nuts, they are considered ‘good fats’ – they have a beneficial effect on cholesterol levels.
- Polyunsaturated fatty acids: These include omega-3 and omega-6. Omega-3 fatty acids, particularly those found in oily fish or linseed, are considered to be especially beneficial to health.
- Trans fats: These are produced industrially during the hydrogenation of vegetable fats – and should be avoided wherever possible (in fast food, pastries and ready-made products).
The key is not to cut out fat entirely – but to get the balance right. A low-fat diet may work in the short term, but can lead to deficiency symptoms in the long term – for example, with regard to the absorption of fat-soluble vitamins.
Proteins – the building blocks of your body
Without protein, there are no muscles. But there’s also no skin, no enzymes, no hormones – and no functioning immune system. Proteins are the structural and functional building blocks of your body.
What many people underestimate: It’s not just athletes who need protein. Anyone who wants to lose weight, recover from exertion or simply stay healthy also relies on a regular and adequate intake of protein. Because: Your body cannot store protein – unlike fat or carbohydrates. It therefore needs a fresh supply every day.
What matters here:
- Amino acids are the building blocks of proteins. There are 20 different types – 8 of which are essential and must be obtained from food.
- Biological value describes how effectively a dietary protein can be converted into the body’s own protein. Animal proteins (e.g. from eggs, fish or quark) generally have a higher biological value than plant-based proteins.
- Combining plant-based sources (e.g. rice and beans) can significantly increase their biological value – an important point for vegans.
Protein requirements vary: In everyday life, 0.8 g per kilogram of body weight is often sufficient; those who are physically active need 1.2–2.0 g – and during periods of intensive training or when building muscle, the requirement may be even higher.
Timing is everything – and the body needs time
An important point that is often overlooked: The body does not adapt to new dietary patterns overnight. Anyone switching from a low-carb diet to one with more carbohydrates, or suddenly increasing their protein intake or reducing their fat intake, will not notice a change straight away. Metabolic processes are finely regulated – and it often takes weeks for enzymes, hormones and cellular processes to adjust.
Patience is particularly important when it comes to macronutrients. Over time, the body learns to use glucose more efficiently, burn fats more effectively or utilise proteins more effectively. A short-term ‘crash diet’ is of little help here – sustainable changes require repetition, consistency and good planning.
It’s all in the mix – and in the mindset
Macronutrients are more than just sources of calories. They are biochemical tools that shape, fuel and repair your body. If you understand how they work, you can specifically influence your energy levels, training performance, recovery and long-term health.
The crucial question is therefore not: ‘Low-carb or high-protein?’
But rather: ‘What do I need – at this stage of my life, with this training goal, and given my individual circumstances?’
And this is precisely where this series comes in.