Minerals


Minerals are inorganic components of our diet. They are absolutely essential for human beings and carry out numerous tasks in the organism. Those minerals of which we generally take in only a few milligrams or even only micrograms are called trace elements. Strictly speaking, the minerals which we absorb in larger amounts and have in our body are called quantitative elements. However, we usually speak simply of minerals. To these belong:

 

 



 

Calcium

Functions in the body
Calcium is needed as a nutrient to build bones and teeth. Accordingly, infants, children and young people, in whom a large amount of bony tissue still has to be formed, require a particularly large amount of calcium. However, the requirement is high in old age as well, when bone mass is continually lost. Large amounts of calcium are necessary to replace this at least partially.

Calcium is important not only for bones and teeth. It performs many other tasks in the blood and in the tissues in conducting electrical stimuli to nerves and muscles, in cardiac function and in coagulation. There are normally no problems with these vital functions even with calcium deficiency, because the missing calcium is then taken from the large calcium warehouse, the bones. Here, of course, it must be replaced.

Recommended intake
According to the recommendations of the German Society for Nutrition, adults should take in approximately 1000 mg of calcium daily.

Important food sources
The best suppliers of calcium in our diet are milk and dairy products. Furthermore, the calcium in these foods is in a form that our body can utilize well. Also some types of vegetables (above all green vegetables such as broccoli), legumes, nuts and whole-grain products supply us with calcium. Mineral water that contains more than 150 mg of calcium per litre (see declaration on the label) is likewise a good source.

Deficiency
Too little calcium intake has consequences particularly for the bones. They lose solidity, become porous and brittle, and the result can be osteoporosis, which occurs frequently especially in women following the menopause. Osteoporosis is often called a typical disease of calcium deficiency, although this is not quite correct. Various other factors play an important role simultaneously in the development of osteoporosis, such as a certain hereditary predisposition, hormonal influences (oestrogens), too little physical activity and an insufficient intake of vitamins D and K. In any case, however, osteoporosis is fostered by inadequate calcium intake.


Phosphorus (phosphate)

Functions in the body
Like calcium, phosphorus - or more correctly phosphate - is necessary for the formation of bones and teeth. In addition, phosphate is a component of every body cell and performs many important functions in the metabolism and as a transporter of energy.

Recommended intake
According to the recommendations of the German Society for Nutrition, adults should take in approximately 700 mg of phosphate daily.

Important food sources
Phosphorus is very widespread in different chemical forms in almost all foods. Moreover, for various reasons in food technology, phosphates are added to many processed foods (e.g. cola drinks).

Deficiency
Because phosphate is so widely found in our diet, a nutritional deficiency practically never occurs.


Sodium

Functions in the body
Together with potassium, sodium maintains the tonus of tissue in the body's cells and between the cells and regulates the water balance. Yet sodium works mainly outside of the cells, while potassium works as its antagonist within the cells. In addition, sodium is important for the stimulation of nerves and muscles, and it plays an important role in the regulation of blood pressure.

Recommended intake
It is estimated that a human being requires at least 500 mg of sodium per day. A recommendation for an optimal intake can hardly be made, however. Rather, the intake of too much sodium is problematic, as this favours the development of high blood pressure.

Important food sources
Table salt consists of sodium chloride, and salt is therefore the most important source of sodium in our diet. One gram of sodium is equal to 1.4 g of table salt.

We eat salt not only by salting our food. At least 50% comes with foods to which salt has been added for reasons of food technology (e.g. to help it keep longer) or of taste. Many processed products are especially rich in "hidden" salt, such as smoked or pickled sausages, cheese, tinned goods, ready-to-eat foods and savoury biscuits.

Deficiency
Under normal conditions, a nutritional deficiency of sodium hardly ever occurs. However, when there is a great loss of fluids, for instance due to sweating, fever, diarrhoea or vomiting, a large amount of sodium is also lost and must be replaced quickly. Recommended in this case are sodium-rich mineral water, vegetable or meat broths or other products containing salt. Some signs of severe loss of sodium are nausea, dizziness and circulatory problems.

As mentioned above, however, too much sodium rather than too little in our diet is a problem. We consume an average of more than 10 g of table salt daily. For a healthy diet that can prevent high blood pressure, experts recommend an intake of not more than 6 g of table salt per day.

To save on table salt, fewer highly processed and ready-to-eat products should be eaten and instead more fresh, unprocessed products. It is better to use less salt for seasoning and to ensure a greater variety of taste with herbs and spices.


Potassium

Functions in the body
Together with sodium, potassium maintains the tonus of tissue in the body's cells and between the cells and regulates the water balance. Yet potassium works mainly within the cells, while sodium works as its antagonist outside of the cells. In addition, potassium is important for the stimulation of nerves and muscles, and particularly for the heart. Potassium also plays an important role in the regulation of blood pressure. In contrast to sodium, large amounts of potassium help to lower high blood pressure.

Recommended intake
Similar to sodium, it is difficult to figure out the optimal intake of potassium. The minimum daily requirement for human beings is estimated to be about 2 g.

Contrary to sodium, however, a high potassium intake is not detrimental for a healthy person but rather desirable, owing to its favourable effect on the blood pressure. In addition, too much potassium is quickly excreted by the kidneys of a healthy person and is therefore not problematic.

Important food sources
Potassium is found - again, in contrast to sodium - mainly in unprocessed foods. Fruits and vegetables, potatoes, legumes, dried fruits and nuts are especially rich in potassium.

Deficiency
A deficiency of potassium due to potassium-poor food is very rare, unless the diet is very one-sided. But similar to sodium, a loss of fluids (e.g. from sweating, diarrhoea, vomiting) also means a loss of potassium, which can lead to deficiency symptoms, such as circulatory and muscle weakness and disturbances of cardiac function. Quick compensation (e.g. with potassium-rich fruit or juice diluted with mineral water) is then necessary.


Magnesium

Functions in the body
Magnesium is particularly important for the muscles. It is active in the transfer of stimuli from nerves to muscles and in muscle contraction. Moreover, it activates numerous enzymes that participate above all in the metabolism of carbohydrates and proteins.

Recommended intake
According to the recommendations of the German Society for Nutrition, adults should take in approximately 300-400 mg of magnesium daily.

Important food sources
Magnesium is contained in many foods. Those particularly rich in magnesium are whole-grain products, green vegetables, legumes, berries and bananas, as well as milk, dairy products and meat. Mineral water passes as magnesium-rich if it contains more than 100 mg magnesium per litre.

Deficiency
Magnesium deficiency can lead to over-excitability of the musculature and thus to muscle cramps (but magnesium deficiency is not always the reason for a muscle cramp!). Marked magnesium deficiency, which would additionally effect various metabolic disturbances, is very rare due to the widespread availability of magnesium in our food.


Chloride

Functions in the body
Together with sodium and potassium, chloride takes part in maintaining tonus in the body's cells and tissues as well as in regulating the water balance. In addition, chloride is a component of gastric acid.

Recommended intake
For chloride, as for sodium and potassium, only the minimum daily requirement can be assessed; it is presumed to be approximately 800 mg.

Important food sources
Chloride is sodium's partner in table salt, and it is therefore contained, as is sodium, in all salted products.

Deficiency
A chloride deficiency is extremely rare, and when it occurs it is usually the result of illness, for example after persistent vomiting.