Carotenoids are a group of wide spread plant specialized metabolites. In addition to having an important role in the plant cell,expanding the spectrum of light absorption and protecting chlorophyll from photooxidative damage, they are also very useful components in human nutrition. Their characteristic structure enables them to have antioxidant activity in animal cells as well. By suppressing reactive oxygen compounds and other harmful products of metabolism, they protect various tissues of the human body. They are an integral part of the retina of the eye and component in synthesis of vitamin A. They can also be found in cell membranes, where their main role is to control the fluidity and permeability of the phospholipid bilayer. Lycopene and β-carotene are the subject of many studies due to their potential preventive effect on various diseases, especially cancer. By regulating gene expression, they reduce the number of tumor cells and promote their apoptosis, and with their antioxidant properties, they reduce the consequences of disease development. The bioaccessibility of carotenoids is a challenging topic for research because it requires an understanding of different mechanisms of absorption and dispersion in tissues.Carotenoids show great potential in the treatment of various diseases and clinical conditions, however, many more studies are needed to fully explain their action and create the possibility of using these compounds for medical purposes.