Vitamins exhibit a wide spectrum of activity. They take part in all vital processes in the organisms and are responsible for young and healthy appearance of the skin. Each of the vitamins is characterized by individual properties and their own way of activity. The aim of the study was to present the most common vitamins in cosmetic products and their influence on the condition of the skin, hair and nails. Vitamin deficiency can cause not only changes and diseases inside the body, but also may impair skin conditionssuch as: altered tone, grayish and bruising around eyes, visible blood vessels, discoloration and lack of elasticity. Synergistic supplementation of vitamins, both oral and external, can improve the appearance of the skin and reduce changes caused by environmental factors.

Reactive oxygen species are formed as a natural product of metabolic processes occurring in the organism or under the influence of external factors. Under homeostasis, they play an important role as a cellular signaling device. During oxidative stress, when they are produced in excess, they can cause damages to proteins, lipids, carbohydrates or nucleic acids. Exposure of cells and extracellular structures to free radicals activate natural mechanisms to eliminate free radicals and their derivatives. The aim of the article was to present what antioxidants are, and how they protect cells against the free radicals. The protective system against the free radicals consists of antioxidant enzymes: superoxide dismutase, catalase, glutathione peroxidases, and reductase. Low-molecular antioxidants such as vitamin C, E, carotenoids, coenzyme Q10, flavonoids, glutathione and melatonin also play an important role.

Cosmeceuticals are preparations that are described in numerous scientific and popular science works as combining the features of a drug and a cosmetic. They are cosmetics, but unlike the traditional ones, they contain a high concentration of active ingredients, usually plant-based, obtained with the use of modern pharmacy, biotechnology and molecular biology techniques. The aim of the study was to present, based on scientific literature, cosmeceuticals as multi-ingredient products and their impact on human skin. Active substances contained in cosmeceuticals cause their more intense action than traditional cosmetics. Therefore, they should be used based on the professional advice of a cosmetologist, pharmacist or doctor.