Minerals: what is the function of minerals?

What are minerals? Why do we need minerals in our diet? Minerals such as magnesium, calcium, selenium and zinc are absolutely essential for numerous processes taking place in our bodies. We need to consume these trace elements and bulk elements through food – and experts maintain that a balanced diet is usually enough to prevent mineral deficiency symptoms.

Minerals are found in a variety of foods, including meat, cereals, fish, milk and dairy products, fruit and vegetables and nuts. They are all necessary for promoting strong bones and healthy teeth, giving us the all-important energy we need on a daily basis and regulating body fluids in our body.

In this article, we dive straight into the heart of the matter: what are minerals exactly, and what is the function of minerals in the body? How do they differ from vitamins, and what are trace and bulk elements? Find out the answers to these commonly asked questions – as well as an overview of some of the most important minerals.

You can also find more information about various specific minerals and mineral deficiencies in our Health Portal:

• Iron deficiency
• Magnesium deficiency
• Selenium
• Zinc deficiency
• Anaemia

What are minerals?

Minerals are micronutrients. This means that they do not provide us with energy – instead, the macronutrients, such as proteins, fats and carbohydrates, do.

Nevertheless, minerals are vital because our body needs them for numerous metabolic processes. Among other things, they are involved in bone formation, the acid-base balance and a healthy immune system. Both mineral concentrations that are too low or too high can pose a danger to our health. 

Minerals vs vitamins: what’s the difference between vitamins and minerals?

When talking about minerals, we should distinguish the difference between vitamins and minerals.

Minerals are inorganic nutrients. Technically speaking, this means, to put it simply, that they have no carbon atoms. One could also say that minerals are not living substances.^[1]

The fact that minerals are considered inorganic substances is where we can identify a distinction between vitamins and minerals. Vitamins, conversely, are organic compounds that have much more complex chemical structures.

Vitamins are often sensitive and can be destroyed when we prepare our food in certain ways. Minerals are much more stable. Only in some cases do they dissolve when heated, and thus their content decreases in the finished dish.

What are trace elements and bulk elements?

Minerals are divided into two categories: trace elements and bulk elements. This distinction is simply based on how high the concentration of a mineral is in the body.

Trace elements are present in smaller amounts; their concentration is (sometimes significantly) less than 50 milligrammes per kilogramme of body weight. These include iodine, fluoride, zinc, selenium, copper, manganese, chromium, molybdenum and iron.

Iron is the exception – it is classed as a trace element, although it is around 60 milligrammes per kilogramme. This is because its function in the body is more similar to trace elements than to bulk elements.

Bulk elements are more concentrated, so we have to take in a little more of them: We have more than 50 milligrammes of them per kilogramme of weight in our body. Bulk elements include calcium, chloride, potassium, magnesium, sodium, phosphorus and sulphur.^[2]

The function of minerals: what do minerals do in the body?

Minerals take on very different roles and functions in your body.

Minerals function as the following:^[3]

• Building blocks – calcium, magnesium and phosphorus, for example, vital components of our bones and teeth. Iodine is needed to produce thyroid hormones.
• Regulators – some minerals function as electrolytes. They control water balance, acid-base balance and blood pressure and transmit electrical stimuli between cells. These include chloride, potassium, sodium and phosphorus.
• Immune system boosters – magnesium, selenium and zinc, among others, play an important role in boosting our immune system.

What minerals are there? 

Let us briefly introduce some of the most important minerals we need on a daily basis. Discover the functions of minerals individually and which foods you should eat to increase your intake of them.

Calcium

The crucial mineral for bone health is calcium. With the help of vitamin D, this mineral is absorbed into our bones, making them more stable. A calcium deficiency or vitamin D deficiency therefore increases the risk of osteoporosis – that is, bone loss – among other things.

The largest amounts of calcium are found in milk and dairy products, especially in hard cheeses such as Emmental and Parmesan. Other sources of calcium are wholemeal bread, amaranth, hazelnuts and Brazil nuts and green vegetables.^[4]

Did you know that calcium is the mineral that is found in the largest quantity in the human body. It makes up to 1.9 per cent of our body weight! The only chemical elements that are more abundant in the human body are oxygen, carbon, hydrogen and nitrogen.^[5]

Chloride and sodium

The electrolytes chloride and sodium regulated various processes in the body, including:

• Water balance
• Acid-base balance
• Blood pressure

Sodium also transmits electrical stimuli in our bodies. We consume both minerals mainly in the form of sodium chloride – that is, common table salt. A little salt is therefore a necessary part of our diet. But be careful not to eat too much of it. A diet that is too salty can increase the risk of cardiovascular diseases. One of the reasons for this is that sodium increases blood pressure.

Potassium

Potassium, also a mineral and electrolyte, serves as a counterpart to sodium. It lowers blood pressure. Nutrition experts therefore advise people to consume more potassium than sodium. Potassium can be found in fruits, vegetables, nuts, rye and spelt.^[6]

Experts advise that adults should receive around 3,500 milligrammes of potassium every day – and that this potassium should come from your diet. Too much potassium can, however, result in stomach pain, nausea and diarrhoea. 

Iron

Blood tastes of iron – this is because this trace element is mostly bound to the red blood pigment haemoglobin. In our blood, iron is especially important for transporting oxygen.

We humans can best absorb iron from animal products – top sources of iron are salted herring, pork and beef liver and eggs. Plant-based foods also contain iron, but it is less readily available to our bodies. So, you need to eat more of them to reveive the same amount of iron. Great sources of iron in plant-based foods include quinoa, lentils, soybeans, porridge and peas.

Did you know that vitamin C improves iron absorption from plant-based sources? For a better iron intake, you can combine iron-rich foods with vitamin C bombs such as peppers, broccoli, currants or citrus fruits.

In the long run, iron deficiency can lead to iron deficiency anaemia, which can trigger symptoms such as paleness, weakness, brittle fingernails and hair loss, among other things.^[3]

Fluoride

You probably know the trace element fluoride mainly as an additive in toothpaste. Fluoride strengthens tooth enamel and is considered one of the most important factors in reducing the risk of tooth decay.

Professionals advise giving fluoride tablets to small children, but to discontinue them as soon as they use fluoride toothpaste. Dentists also advise adults to use toothpaste with fluoride to protect their teeth.^[7]

Like many substances, fluoride is dangerous in excessive quantities – but you can hardly consume such quantities in your everyday life. For a fatal dose, a 15-kilogramme child would have to devour twelve tubes of fluoride toothpaste in one go. The consequences of poisoning are usually abdominal pain and nausea.^[1]

Iodine

Half of the iodine we carry in our bodies is stored in our thyroid gland. There, with the help of iodine, thyroid hormones are produced. These, in turn, are important for growth, bone health, brain development and energy metabolism. Iodine deficiency can therefore lead to mental developmental disorders, among other things.^[8]

In many countries, the soil contains less and less iodine. This lack of iodine transfers to the plants and animals that live on and off the soil – and thus to the food we eat.

Saltwater fish, dairy products and certain algae are still rich in iodine. These are not exactly foods that are on everyone’s shopping list. That is why it is common practice in about 70 countries worldwide to add iodine to table salt. Iodised table salt helps to cover our daily iodine requirement. That is why international health organisations such as WHO recommend the use of iodised salt.^[9]

Magnesium

Above all, the mineral magnesium is essential for energy production in our bodies, as well as for promoting healthy bones and teeth.

Another function of magnesium is to relax the muscles. If you suffer from calf cramps, for example, this could be due to an excess of calcium compared to magnesium, leading the muscles to tense and cramp up.

Magnesium is found primarily in plant-based foods, especially pumpkin and sunflower seeds, almonds, quinoa and porridge, but also in whole grains, legumes, bananas and cocoa.^[10]

Molybdenum

We need the trace element molybdenum, so that our bodies can produce certain important enzymes that are responsible for repairing and producing genetic material in our bodies.

Good sources of the mineral include foods that grow under ground, such as potatoes or carrots. Experts advice that your molybdenum intake should come from a healthy, balanced diet.

Phosphorus

Phosphorus is easily confused with phosphate. But phosphorus is the mineral that our body needs. Phosphates are our source of phosphorus – that is, the salts of phosphoric acid that we consume in our food.

Phosphate is found in a wide variety of foods. The greatest concentrations are found in protein-rich animal products, such as meat, fish, eggs and milk.

Phosphorus and calcium are the substances that are absorbed by our bones together to make them strong. Phosphorus is also involved in energy metabolism and in maintaining the pH value in the acid-base balance.^[13]

Selenium

Selenium is an essential trace element. Your body stores only up to 30 milligrammes of the mineral, most of it in the thyroid gland and muscles. Among other things, we need it for producing thyroid hormones, a healthy nervous system function and producing sperm.

You can get selenium from tuna, eggs, cheese, nuts and seeds. Brazil nuts are particularly rich in selenium.^[3]

Caution: Brazil nuts can contain a high level of radioactive radium. Experts recommend eating no more than two Brazil nuts a day to boost your selenium levels.^[14]

Selenium also binds with mercury, so it can help our body eliminate the toxic heavy metal and prevent mercury poisoning.^[15]

Zinc

Zinc is a coenzyme, a molecule that performs tasks throughout the body. It regulates blood sugar, is involved in producing testosterone, activating proteins for muscle growth, and boosting our immune system – as well as in cell division, wound healing and much more.^[16]

The best way to optimise your zinc intake is to combine plant-based and animal sources of zinc. Your body can generally absorb zinc better from animal products, such as cheese, eggs, offal and beef. Zinc-rich plant-based foods include flaxseed, cocoa powder, sunflower seeds, whole grains and legumes.^[17]

Sources

^[1] European Food Safety Authority, ‘Tolerable upper intake levels for vitamins and minerals’, Parma: European Food Safety Authority, 2006.

^[2] Zoroddu M. A., Aaseth J., Crisponi G., Medici S., Peana M., Nurchi V. M., ‘The essential metals for humans: a brief overview’, J. Inorg. Biochem., vol. 195, pp. 120–129, June 2019, doi: 10.1016/j.jinorgbio.2019.03.013.

^[3] Elmadfa I., Ernährungslehre, 3rd edition, Verlag Eugen Ulmer Stuttgart, 2015.

^[4] Schumann L., Martin H.-H., Keller D. M., ‘Calcium, Milch und Knochengesundheit’, Ernähr. Im Fokus, 2014.

^[5] World Health Organization und Food and Agriculture Organization of the United Nations, Vitamin and mineral requirements in human nutrition, 2nd edition, Geneva : Rome: World Health Organization ; FAO, 2004.

^[6] ‘Deutsche Gesellschaft für Ernährung e. V. | dge.de,’ available at https://www.dge.de/, accessed on 17 March 2020.

^[7] Bundesinstitut für Risikobewertung, ‘Für gesunde Zähne: Fluorid-Vorbeugung bei Säuglingen und Kleinkindern’, 2018, doi: 10.17590/20180531-085715-0.

^[8] Bundesinstitut für Risikobewertung, ‘Jod’, available at https://www.bfr.bund.de/de/a-z_index/jod-4600.html, accessed on 24 March 2020.

^[9] de Benoist B. et al. Iodine status worldwide WHO global database on iodine deficiency. Geneva: World Health Organization, Department of Nutrition for Health and Development, 2004.

^[10] Heseker H., Stahl A. ‘Magnesium. Physiologie, Funktionen, Vorkommen, Referenzwerte und Versorgung in Deutschland’, Ernähr. Umsch., 2011, available at https://www.ernaehrungs-umschau.de/print-artikel/12-07-2011-magnesium/, accessed on 7 May 2018.

^[11] Deutsche Gesellschaft für Ernährung (DGE), Österreichische Gesellschaft für Ernährung (ÖGE), Schweizerische Gesellschaft für Ernährung (SGE, D-A-CH-Referenzwerte für die Nährstoffzufuhr, 2. edition, Bonn.

^[12] Schwarz G., Mendel R. R., Ribbe M. W. ‘Molybdenum cofactors, enzymes and pathways’, Nature, vol. 460(7257), pp. 839–847, August 2009, doi: 10.1038/nature08302.

^[13] Holleman A. F., Wiberg E., Wiberg N. Lehrbuch der anorganischen Chemie. Walter de Gruyter, 2007.

^[14] ‘Natürliche Radioaktivität in der Nahrung’, Bundesamt für Strahlenschutz, available at https://www.bfs.de/DE/themen/ion/umwelt/lebensmittel/radioaktivitaet-nahrung/radioaktivitaet-nahrung_node.html, accessed on 1 April 2020.

^[15] Bjørklund G. ‘Selenium as an antidote in the treatment of mercury intoxication’, Biometals Int. J. Role Met. Ions Biol. Biochem. Med., vol. 28(4), pp. 605–614, August 2015, doi: 10.1007/s10534-015-9857-5.

^[16] Dr. Schuchardt J. P. ‘Die Bedeutung von Eisen, Zink und Selen in der Ernährung des Menschen’, Ernähr. Umsch. 57, 2010.

^[17] Souci S. W., Fachmann W., Kraut H., Andersen G., Soyka K., Deutsche Forschungsanstalt für Lebensmittelchemie, Lebensmitteltabelle für die Praxis Der kleine Souci/Fachmann/Kraut. Stuttgart: Wissenschaftliche Verlagsgesellschaft Stuttgart, 2011.