INTRODUCTION
A distinctive feature of non-alcoholic tonic (energy) beverages is the ability to have a tonic effect on the functional activity of individual organs and tissues of a human body as a whole, the effectiveness of which may vary depending on the physiological state, age and sex.
According to the results of numerous studies, the main consumers of tonic (energy) beverages are men aged 30-35 years. This is largely due to the peculiarities of life and social and community activities of the male population, in particular the need for more emotional stimulation, overcoming tiredness and stress, as well as compensation for the lack of so-called "healthy" food [1, 2, 3, 4, 5, 6].
Consumption and sales in this segment are growing. According to the results of previous studies that we reviewed, the level of consumption of tonic (energy) beverages in Russia will be increased by 1.5 liters per capita compared to 2014, and it will be 2.9 liters by 2017. In highly developed countries, such as the USA, Germany, the UK, during the period from 2014 to 2017 level of tonic (energy) beverages consumption will be increased by 10.6 liters, 0.9 liters, 1.5 liters per capita respectively [7].
One of the main components of tonic (energy) beverages is caffeine. Its attractiveness for producers and consumers is stipulated by the availability and quite pronounced stimulating effect on mental and physical abilities of a person, which helps to keep fit during tiredness [8]. After intake of beverages with caffeine tiredness and drowsiness are temporarily eliminated or reduced. Caffeine has a great influence on the highest nervous activity of an organism, which largely depends on the applied dose and component and the type of humans nervous system. When used in small doses it is dominated by the stimulating effect, in large - depressing.
The results of the previous studies to determine presence and duration of tonic effect have confirmed the fact, that caffeinated beverages have a tonic effect lasting up to two or three hours, enhance efficiency and rapid involvement in the process, increase mental and physical performance. However, after drinking tonic (energy) beverages some deterioration of health is possible with the development of unpleasant subjective sensations (knock on his temples, nausea, physical weakness) and increased systolic and diastolic blood pressure, pulse rate [9]. Adverse effects occur with long-term consumption of caffeine-containing beverages in doses greater than 400 mg / day.
