To stay healthy, the body needs around 50 nutrients in sufficient quantities, including carbohydrates, fat and protein as well as vitamins, minerals and trace elements. Otherwise there is a risk of complaints.
Without food, man would starve to death within a month. The body gets all the nutrients it needs to survive from food. He works like a power plant and burns the substances so that they provide him with energy . And he needs the materials all the time, regardless of whether the person is resting or working hard.
About half of the energy that the body gains from food is converted into heat. It uses a fraction in the excretions and to shed dead body cells, another part it needs for digestion itself. The rest, that is about 40 percent, is used, for example, for the heart, breathing and physical activities – or it stores it. In addition, the absorbed nutrients serve as building blocks for his cells.
People have to ingest around 50 nutrients through food in order to stay healthy. The most important sources of energy are carbohydrates in the form of starch and sugar. They are the fuel that feeds muscles , nerves and the brain . Fats are also an indispensable source of energy. They also cushion the internal organs and form the material from which the elastic sheaths of the cells are made. The body uses the protein in the food as if from a construction kit: It uses it to assemble muscles , skin , hair, hormones or immune cells.
Humans also have to take in vitamins and minerals in very small amounts . All vitamins and many minerals are essential, i.e. vital, and that means that humans depend on taking them in through food, as the body cannot usually produce them itself.
Then there are the phytochemicals that are not officially part of the nutrients. These substances primarily help the plant itself, for example in repelling pests or, as a coloring or fragrance, attracting animals to pollinate flowers. But they also have many health-promoting effects for humans.
Carbohydrates and fiber
The body needs carbohydrates for quick energy production. The brain uses them almost exclusively. If the person has hypoglycaemia, they feel tired and exhausted and have difficulty concentrating.
If carbohydrates are missing over a long period of time, the body attacks its fat reserves. If both are not available, the substance is at stake: the body breaks down protein, muscles dwindle. Carbohydrates are not really essential because the body can produce them on its own. Nevertheless, it is an important part of the diet.
Chemically speaking, all carbohydrates are sugars. There are simple sugars such as grape sugar (glucose) or fruit sugar (fructose), but they can combine to form double or multiple sugars. A double sugar is, for example, household sugar (sucrose), which consists of glucose and fructose. Multiple sugars, especially starch, are made from long chains of single sugars that are found in cereals or potatoes, for example.
Various carbohydrates also combine to form chains that can not be broken down by the digestive system and are therefore indigestible. These are the so-called dietary fibers. They are found in plant foods. When foods contain sugar or starch together with fiber, for example in fruit and whole grain products, these carbohydrates fill you up better and cause blood sugar to rise more slowly than foods that contain sugar or starch without fiber, such as in sweets or white bread.
In addition to carbohydrates, fat is an important supplier of energy. It is embedded in the membrane of cells and it is involved in the cell’s metabolism. The body needs the fat to absorb vitamins A, D, E, K and carotene (the precursor of vitamin A) . The fat also protects him from the cold and supports internal organs. Man could not survive long without fat. He would lack energy reserves that his body can fall back on in an emergency, because energy can only be stored in the form of fat. This is actually good because he has important energy reserves in an emergency – but bad when the cushions get too big and excess weight results.
But that doesn’t mean that too much fat makes you fat. Obesity can also result from too many carbohydrates, because an excess of carbohydrates is converted into fat and stored in fat pads.
In moderation, fat is essential. The decisive factor is the type of fatty acids consumed . Experts differentiate between saturated, monounsaturated and polyunsaturated fatty acids. Then there is the fat-like substance cholesterol .
Egg white (protein)
In order to produce cells, muscle fibers , bones, organs, hormones or blood, humans have to ingest protein through food. The body then converts these important building blocks into its own proteins. The diet should therefore consist of around 10 to 20 percent protein-containing foods such as cheese, meat, eggs, milk or milk products and fish. Vegetable protein is mainly found in cereals, potatoes, nuts, pulses and soy.
As an energy supplier, however, protein is more of a late bloomer. It takes a lot of time to break down protein. The building material is also the body’s last reserve, which it only attacks in an emergency – for example in times of hunger or serious illnesses. A lack of protein can lead to growth damage, muscle wasting or changes in the blood count.
The body produces twelve amino acids itself
The protein contained in food is digested by enzymes and broken down into 20 different amino acids. These migrate through the small intestine into the blood and are assembled in the cells in a specific sequence to form body proteins.
The organism can produce eleven of these 20 amino acids itself, nine can only be obtained from food. So that protein can be used and built up correctly, all of these amino acids must be present in the correct ratio, otherwise the protein build-up will only work in a halt. This is why a varied diet is important: Grain and dairy products, meat, fish and eggs contain all the important amino acids in sufficient quantities. Vegetarians can meet their needs with grains, nuts and dairy products.
Vitamins are organic substances that the body needs for vital functions. Only very small amounts of the vitamins are required because the body does not burn them and does not build them into the cells. Rather, vitamins maintain the chemistry in the body by regulating many metabolic processes, for example the formation of hormones, the construction of body tissue. They support the immune system and help detoxify the body. The organism cannot produce vitamins itself, or only to a very limited extent. Humans therefore have to take them in through food.
Some vitamins, dissolved in water, get into the blood through the intestine : these are the water-soluble vitamins . The blood transports them to where they are needed. However, the body can hardly store them. Vitamins that he does not need are eliminated with the urine. The water-soluble vitamins help convert carbohydrates , fats and protein.
- Vitamin C strengthens the connective tissue.
- Vitamin B1 (thiamine) strengthens the condition.
- Vitamin B2 (riboflavin) gives energy.
- Vitamin B3 (niacin) strengthens the skin and nerves.
- Vitamin B5 (pantothenic acid) stimulates the metabolism.
- Vitamin B6 (pyridoxine) supports the immune system.
- Vitamin B7 (biotin) is needed by the skin and hair.
- Vitamin B9 or B 11 (folic acid) is important for the embryo and helps to form new blood.
- Vitamin B12 (cobalamin) helps with cell growth.
Fat-soluble vitamins, on the other hand, do not mix with water. You need fat as a transport medium, otherwise the body cannot use it.
- Vitamin A is important for the eyes.
- Vitamin D strengthens the bones.
- Vitamin E protects against tissue-damaging substances, so-called free radicals,
- Vitamin K is involved in blood clotting.
Vitamin tablets only for those who don’t like fruit
Vitamin tablets can be useful if you cannot otherwise absorb enough of these substances, for example if you are on a strict diet, suffer from illness or after an operation. Even in pregnancy , in which the vitamin requirement is significantly increased, supplemental vitamin tablets may be required. Please ask the attending physician here. For those who don’t like fruit and vegetables, these preparations are better than completely avoiding vitamins.
However, the artificial vitamins are not an adequate substitute for the natural substances. When pressed in tablet form, vitamins can work differently than in the fruit. In it, they often develop or intensify their effect in interaction with the other ingredients.
The body cannot produce minerals itself. They must therefore be supplied through food or drinks. They only make up a negligibly small proportion of the body mass, but they fulfill vital functions.
One of the most important minerals is calcium, which strengthens bones and teeth . Sodium and potassium regulate the body’s water balance and make the muscles work. Magnesium activates more than 300 enzymes and controls the interaction of nerves and muscles.
But the body does not need the same amount of every mineral. The body needs a higher dose of the so-called bulk elements such as sodium and calcium: with sodium it is at least 500 milligrams per day, with calcium as much as 800 to 1,000 milligrams.
The trace elements such as iron and zinc are different : the body only needs very small amounts of these. A few milligrams, sometimes just a few micrograms, are sufficient.
Secondary plant substances
Plants are not just made up of carbohydrate fibers, water, fat and protein. They also store tiny amounts of substances that they need to survive: they ward off pests, use dyes or fragrances to attract animals to pollinate or regulate growth. The number of these different plant substances is estimated at 60,000 to 100,000, but only a fraction of them has been researched in more detail.
Some of these so-called secondary plant substances are healthy for humans: They are not miracle cures, but they have healing properties. Some of them may prevent cancer and cardiovascular disease, lower cholesterol, or act as antioxidants. Secondary plant substances are found in many types of vegetables and fruits. Cereal products, potatoes and aromatic plants also contain these important substances. They probably only develop their health-promoting effect in interaction with other components of the plant.
It’s not just the carrot that contains carotenoids
Alpha and beta carotene are among the most important secondary plant substances. These are precursors of vitamin A. There are plenty of carotenoids in carrots, tomatoes, grapefruit, red peppers and apricots. They’re also found in green vegetables like broccoli, spinach, and kale – about ten times more than in a comparable amount of fruit.
If you eat enough fruits and vegetables there is no need to fear shortages. However, too much carotene has side effects: The skin turns slightly yellow at times. In rare cases, eating too much carotene can affect the liver. If the consumption is reduced to the usual amounts again, the values normalize quickly. You should be careful with beta-carotene in pill form. Research has shown that it can increase the risk of lung cancer, especially in smokers.
Polyphenols protect against hardening of the arteries
The polyphenols include flavonoids and phenolic acids. These plant substances prevent pests from attacking a plant. Embedded in the outer layers of the leaves and peel, the polyphenols protect the underlying tissue. They are particularly common in apples, but also in onions, endive salad, blue grapes, cocoa, green tea and red wine. Red wine may protect against cardiovascular diseases because of its flavonoids.
If possible, fruit and vegetables should be eaten unpeeled, as the polyphenol content is highest under the skin. It gradually decreases with prolonged storage.
Phytoestrogens act like the female sex hormone
Phytoestrogens, i.e. plant hormones, are mainly found in whole grains and oilseeds such as soybeans and flaxseed. Ingested through food, they compete with the female sex hormone estrogen in the body. They mimic the hormone or block it by docking on the body’s own estrogen receptors. However, it has not been proven whether these plant substances actually inhibit breast and prostate cancer, both of which are dependent on hormones.