Nutrition is how your body takes in food and turns it into the substances it needs to work. Those substances are called nutrients, and your body draws on them for energy, for growth and repair, and for the many quiet processes that keep you going. The World Health Organization and Cleveland Clinic describe it in similar terms: nutrition is the process of eating, absorbing and using food so that the body is adequately supplied.
It is common to have a rough sense of what eating well means and still find the detail confusing. This article sets out what nutrition is, which nutrients the body needs, what balance actually means, and why any of it matters. It does not ask you to overhaul your plate or turn eating into a set of rules to follow perfectly.
What is nutrition?
Nutrition is the process of eating and absorbing food, then breaking it down into nutrients the body can use. Nutrients are the chemical substances found in food. Good nutrition supplies energy and the raw material for growth, repair and everyday function, and the WHO frames a healthy diet as one that meets the body’s needs across the whole of life.
It helps to separate two words that are often used as if they mean the same thing. Nutrition is the broad process of nourishment. A diet is simply the pattern of what a person eats. You look at your diet in order to improve your nutrition: the two are related, but they are not the same.
What nutrients does the body need?
There are six broad classes of nutrients, and a good diet combines all of them, according to Cleveland Clinic: carbohydrates, fats, proteins, vitamins, minerals and water. The first three are grouped as macronutrients, because the body needs them in large amounts. Vitamins and minerals are micronutrients, needed in much smaller amounts. Water sits alongside both and is itself essential.
Macronutrients
Macronutrients are the body’s main source of energy. There are three:
- Carbohydrates are the primary energy source for the body. The WHO advises that most of them come from whole grains, vegetables, fruit and pulses rather than refined sources.
- Fats are essential for the proper functioning of cells, and two fatty acids can only be obtained from food. Quality matters: the WHO notes that unsaturated fats are preferable to saturated fats and to trans fats.
- Proteins provide the building blocks for structures such as muscle, as well as for functional molecules like hormones and enzymes.
As a rough guide for adults, the WHO describes carbohydrates making up around 45 to 75% of daily energy, a minimum of 15% of daily energy from fat with a limit of 30% or less for adults, and protein at around 10 to 15%. These are population ranges to inform public health, not personal targets to measure at every meal, and individual needs vary.
Physical activity can change both total energy needs and the balance of macronutrients. People who exercise regularly may need more carbohydrates to fuel activity and more protein to support recovery, particularly when training is frequent or intense. Individual needs depend on factors such as the type and volume of exercise, body size and personal goals, so athletes may benefit from tailored advice from a qualified nutrition professional.
Micronutrients
Micronutrients are vitamins and minerals. There are about 30 in total, roughly 13 vitamins and 16 minerals, and the body needs each of them in small amounts for growth and health, according to the WHO. They do not provide energy, but they support functions from metabolism and immunity to bone health, and a shortage of even one can cause serious problems such as anemia. You need less of them than macronutrients, but they are no less important.
Water
Water is easy to overlook and is an essential nutrient in its own right. Cleveland Clinic describes it carrying nutrients and oxygen to your cells and supporting nearly every process in the body.
How nutrition needs change through life
Nutrition is not one fixed formula. Cleveland Clinic describes needs shifting across a lifetime: breast milk or formula meets most of a baby’s needs for the first six months, solid foods are introduced gradually after that, and adults and older adults need a different combination again.
Some differences are specific. Cleveland Clinic notes that women who menstruate may need more iron because iron is lost through menstruation, and that pregnancy and childbirth can contribute to iron-deficiency anemia. Some older adults experience a reduced appetite, which can make it harder to meet their nutrient needs. Adequate vitamin D and calcium remain important for bone health.
Health changes the picture too. Conditions affecting appetite, swallowing or absorption can lead to undernutrition, either of macronutrients or of a single vitamin or mineral, and the WHO reports that micronutrient deficiencies remain common worldwide. This is one reason general guidance only takes you so far. It is written for a healthy adult population, and it is not designed for pregnancy, childhood, older age or a diagnosed condition.
What does a balanced diet mean?
Balance is the word people reach for and rarely define. The WHO sets out four core principles of a healthy diet that hold in any culture or cuisine: adequacy, which means meeting nutrient needs without exceeding them; balance, which means matching energy intake to what the body uses, across carbohydrate, fat and protein; moderation, which means limiting foods and ingredients that can harm health in excess; and diversity, which means eating a wide variety of foods within and across food groups.
A diet that holds to these four tends to supply what the body needs without much counting. It is a pattern held over weeks, not the verdict on any single meal.
Why nutrition matters
Diet plays a large part in shaping health. The WHO states that a healthy diet helps to protect against malnutrition in all its forms, as well as against noncommunicable diseases including diabetes, heart disease, stroke and cancer, and that an unhealthy diet is among the leading global risks to health. Cleveland Clinic similarly reports that proper nutrition can reduce the risk of diabetes, heart disease and stroke, and that it supports healing and mental health.
None of this is a guarantee. Diet is one factor among many, alongside genetics, physical activity, sleep, income and access to food. What the evidence supports is that a better pattern, sustained over time, is associated with lower risk. It is not that any single food prevents or cures disease.
The WHO also notes a broad shift in how people eat: many now consume more highly processed foods high in fats, free sugars and salt, and do not eat enough fruit, vegetables and fibre. Understanding nutrition is partly about recognising that pattern in your own eating, without judgement.
How much is enough? A note on numbers
It is fair to want figures. For adults, the WHO suggests at least 400 grams of fruit and vegetables a day (about five portions), keeping free sugars under 10% of daily energy (roughly 50 grams, or about 12 teaspoons, for someone eating around 2000 calories), and salt under 5 grams a day (about a teaspoon). Both the type and the amount of fat matter.
These are population figures, meant to guide public health rather than to be policed at every meal. What a given person needs shifts with age, sex, activity, pregnancy and health, which is why general numbers only take you so far.
Numbers can be useful, and for some people they become a source of stress. If thinking about food, weight or eating is causing you distress, that is a good reason to seek individual support rather than stricter rules. Your doctor is a reasonable first point of contact and can refer you on.
Nutrition in Switzerland
The Swiss Dietary Recommendations, illustrated by the Swiss food pyramid from the Swiss Society for Nutrition and the Federal Food Safety and Veterinary Office (updated 2024), translate these principles into everyday portions. They suggest around 1 to 2 litres of unsweetened drinks a day, five portions of vegetables and fruit (three of vegetables, two of fruit), three portions of cereals or potatoes with at least half wholegrain, and daily protein and dairy.
A simpler version, the balanced plate, suggests filling two fifths of the plate with vegetables and fruit, two fifths with carbohydrate and one fifth with protein. The guidance is written for healthy adults and is meant as orientation, with amounts adapted to the individual.
How do you get personalized nutrition support in Switzerland?
For general, reliable guidance, the Swiss Society for Nutrition publishes free recommendations and tools that anyone can use, and they cover most everyday questions well.
In Switzerland, the profession recognised for individual nutritional counselling is the dietitian, the dipl. Ernährungsberater or Ernährungsberaterin (BSc or HF), recognised under the health-insurance ordinance. Where there is a medical reason and a doctor’s prescription, basic insurance contributes to that counselling, subject to your deductible and coinsurance.
Individual questions are different from general reading: a health condition, pregnancy, a restricted diet, or simply wanting guidance that fits your life are usually better answered one to one. If you would like that, you can arrange a nutrition consultation with ahtida Health, which is a structured digital medical clinic and provides care in Nutrition among its areas. Consultations are available in German and English.
Nutrition and weight management overlap. Energy balance sits in both, and where weight is being looked at with medical supervision, dietary change is usually part of the same plan rather than a separate exercise. ahtida Health provides care in both areas, so if that is closer to your situation you can read about medically supervised weight management instead.
Frequently asked questions
Is nutrition the same as a diet?
No. Nutrition is the whole process of nourishing the body, from eating to absorbing and using nutrients. A diet is the pattern of what you eat. You can change your diet in order to improve your nutrition.
What is the difference between macronutrients and micronutrients?
Macronutrients (carbohydrates, fats and proteins) are needed in large amounts and provide energy and structure. Micronutrients (vitamins and minerals) are needed in small amounts and support many functions, from immunity to bone health. Both are essential.
How many nutrients does the body actually need?
There are six broad classes: carbohydrates, fats, proteins, vitamins, minerals and water. Within those, the WHO counts about 30 micronutrients, roughly 13 vitamins and 16 minerals, alongside the macronutrients the body needs in larger amounts.
Do I need supplements?
The WHO frames a varied diet of nutrient-dense foods as the foundation of good nutrition, and for many people that is enough to meet their needs. Supplements may have a role where there is a specific need, an increased requirement or a diagnosed deficiency. If you are unsure, it is worth asking a qualified professional rather than guessing.
Who can help with nutrition questions in Switzerland, and does it cost anything?
For individual counselling, the recognised profession in Switzerland is the dipl. Ernährungsberater or Ernährungsberaterin (BSc or HF). General public guidance from the Swiss Society for Nutrition is free to use, while individual counselling is a professional service: with a doctor’s prescription and a recognised dietitian, basic insurance contributes, subject to your deductible and coinsurance, and otherwise you pay privately.
A calmer way to think about it
Nutrition is less about perfection than about a pattern you can keep. Knowing what nutrients do, and what balance means, is enough to make small, steady choices without anxiety, and if you want a structure to build from, our guide to creating your own diet plan is a practical next step.
If and when you want to look at your own nutrition more closely, you can talk it through in a nutrition consultation with ahtida Health. You can use the appointment to ask questions and explore changes that fit your health, routine and preferences.
References
- World Health Organization. Healthy diet. Fact sheet. 26 January 2026.
- Cleveland Clinic. Nutrition. Health Library. Last reviewed 18 March 2025.
- Federal Food Safety and Veterinary Office (BLV) and Swiss Society for Nutrition (SGE / SSN). Swiss Dietary Recommendations and the Swiss food pyramid. 2024.
- Federal Council. Ordinance on Health Insurance (KVV), Art. 50a, recognised dietitians. Consulted 14 September 2026.