Food supplements are more and more popular. However, there are many widespread fables among consumers relating to their safety and effectiveness. Consumers often confuse them with medicaments. Some producers even support this false belief and on the packaging or in commercials, they promise even wonder results – for example treat of asthma or psoriasis, decrease of cardiac diseases risk, prevention of cancer, elimination of side effects of chemotherapy or even reduction of growth of tumours. Nevertheless, food supplements differ from other foodstuffs only in high content of vitamins, mineral substances or other substances with nutritional or physiological effect. The aim of their consumption is to supplement routine diet to a level positively affecting the health condition of the consumer. Some food supplements thus may have positive effects; however, they cannot solve any health problems entirely. Food supplements do not cure.