From year to year, we observe constantly growing revenue from the sale of supplements and functional food for athletes. The increased interest in their use raises many questions concerning the choice of products, portions, in addition in the case of athletes with type 1 diabetes – how they affect the level of glycaemia. In the group of people under 18 with diagnosed type 1 diabetes, the properly selected supplementation, which will not cause undesirable effects, is even more important. This publication aims to summarize the current reports on nutrients that come from: the present scientific knowledge, information on the labels, and information available on the websites of the most popular companies producing nutrients on the Polish market.