The basis for professional high-performance sports is provided at an early age. Not only age- related physiological developments, like for example rapid growth, hormonal changes in puberty and so on, but also regular and intensiv sportive activities require an adequate nutrition that suits the individual requirements of the young athletes. This paper is supposed to contribute to the determination of the nutritional situation of young high-performance athletes of various disciplines. As a part of this thesis in the first part of the survey the nutritional status of 99 athletes between the age of 11 and 22 years were examined with the help of a computer-based evaluation (Prodi 4.5/03 expert) of 7-day-diet-records. Subsequently the concentration of insufficiently provided vitamins and minerals in the blood plasma was analysed in order to acquire more information on the current supply status of the athletes. Additionally the status of fatty acids was specified by the composition of fatty acids in the phosphorlipids of erythrocyte membrane. More clinically-relevant parameters like the concentration of hemoglobin und creatinin, the enzymic activity of the glutathione peroxidase as well as the concentrations of the thyroid gland-hormons T4, fT4 und T3 in the blood plasma were determined. The results of the diet-records and the blood- analyses were the following: The athlet's energy intake was in comparison to the extimated energy consumption clearly lower. As for the absolute amount of needed carbohydrates that was determined for each athlete on the basis of the estimated energy demand, the male and female athletes took up to less carbohydrates and some athletes to less fat in their nutrition. Particulary the intake of n-3-fatty-acids seemed to be to low. 55 % of the athletes were - even considering ß-carotin - not able to obtain the DGE's recommendation of intake of retinol, which resulted in 68 % of the athletes, especially those of technically-compository-disciplines showing an insufficient concentration of retinol in the blood plasma, which indicates that several athletes are supplied with retinol below the optimal level. 38% of the athletes were not able to cover their demand of α-tocopherole, 14% showed an insufficient intake of Vitamin B12 almost all athletes an insufficient intake of folic acid. Nevertheless a sufficient supply of the athletes was presumed due to the normal concentrations of α-tocopherole, Vitamin B12 and folic acid in the blood plasma of the athletes. Summing up, it may be said that for the majority of young athletes the supply of retinol as well as of n-3-fatty-acids seems insufficient. Besides an insufficient intake of energy and carbohydrates, in future, studies will have to pay more attention to these results. In the second part of this paper 36 athletes of different endurance- and power-sport-disciplines bet-ween the age of 13 and 23 took part in a zinc supplementation that lasted six weeks. The effect of a different zinc status as well as the effect of a zinc supplementation lasting six weeks of athletes with different zinc status on selected hematological parameters (hematokrit, hemoglobin, MCHC, CRP, haptoglobin and the resistance of hemolysis of the erythrocytes to hypotonic NaCl-solutions), on the zinc status (concentration of zinc, zinc-binding-capacity and enzyme activity of the alkaline phosphatase) in the blood plasma as well as the effect on the immunological status of the athletes (IgG, IgM, leucocytes and their subpopulations, T-lymphocytes, which produced in vitro the cytokines INF-γ, TNF-α and IL-2) was examined. As for the effect of zinc, the following results were found: Group 1, beginning with the lowest concentration of zinc in the blood plasma (+- and CD8+-cells. However, there was a significant increase of the absolute and relative numbers of monocytes for the athletes of all three groups. Neither before nor after the intake of zinc there were any significant differences as to the ability of the T-cells, to produce cytokines INF-γ, TNF-α and IL-2 in vitro. After the zinc supplementation a significant decline of the IFN-γ- und IL-2- producing, as well as a significant increase of the TNF-α- producing T-lymphocytes independent of the status of zinc at the beginning, could be determined for all three groups. Because of the fact that not only group 1, but all three groups showed mostly the same significant changes after the intake of zinc, no definite effect due to the intake of zinc can be stated. It needs further surveys in future in order to understand the connection between the status of zinc and the immunological status better.