Food supplements are designed as additions to the diet. They are products that contain vitamins, minerals, amino acids (building blocks of protein), enzymes (complex proteins that speed up biochemical reactions) or other ingredients with a nutritional or physiological effect. Medicines, on the other hand, are substances that target a particular part of the body that causes pain or is affected by a particular disease. Their purpose is to cure, maintain, and improve the current state of the body or prevent disease.
Supplements can give us extra nutrients when our diet is deficient or certain conditions (such as cancer, diabetes, or chronic diarrhoea) create a deficiency. People also take food supplements to maintain their general health, to support mental and sports performance, and to provide support for the immune system. Unlike most medicines, supplements are commercially available and can be bought without a prescription.
We can get all the vitamins, minerals, and other substances we need through a healthy diet. However, research has shown that this happens quite rarely. Essential nutrients, including calcium, potassium, magnesium, and vitamins A, B, C, and D, have been shown to be lacking in the diets of economically developed countries [Spirichev 2010]. Nutrients in supplements have also been found to play an important role in maintaining normal physiology and human health. They are also necessary for improving body immunity and can be effective against viral infections, including COVID-19 [Thirumdas 2021].