The increasing interest in flavonoids means higher demand for the complex and synthetic knowledge about those substances. The following study is an overview of the contemporary knowledge about the mentioned substances, and hopefully it will magnify this topic. Flavonoids are the ingredients of many nutrition substances and a vital diet element. They are also a group of many medicines with different influence on live organisms. At the moment, there are over hundreds of bio-flavonoids identified. The phenol compounds are used as natural drugs in the cases of various sicknesses of blood, breathing, food, and urinary circuit, and in dermatology as well. The existence of these compounds in the diet, especially maintenance of their proper consumption level, is a very important element in the prevention of many diseases, such as atherosclerosis. The intensity of experimental studies on flavonoids in the last decade (mainly studies on cell cultures) showed varied attributes of these compounds. The results give hope for the use of flavonoids in prevention and neoplasmatic treatment. Phenol compounds as antioxidants may affect in many different aspects: direct reaction with free radicals, scavenging free radicals, growing dismutation of free radicals to the compounds with much lower reactiveness, chelatation of pro-oxidant metals (mainly iron), delaying or strengthening many enzymes. What is more, they can strengthen the functionality of other antioxidants, such as vitamins resolving in fat, and low-molecular substances resolving in water. The wide spectrum of the functions of flavonoids and their synthetic derivatives gives hope for the research of new chemical compounds (drugs) with exploratory characteristics.