Grazing vegetation is rich in carotenoids, vitamins and n-3 fatty acids, which enter the body of grazing individuals and thus enrich their meat with these substances, thereby increasing not only the quality of products, but also the health of animals and people. To ensure a higher intake of grazing vegetation, it is advisable to apply restriction to the chickens, i.e. reduce the amount of the cereal mixed feed. The level of restriction must be balanced so that there is no unwanted drastic reduction of performance, but only within tolerated limits. In medium-growing Hubbard JA 757 cockerels, restriction of cereal diet by 20% was sufficient to increase lutein and zeaxanthin content and decrease n-6/n-3 ratio and atherogenic and thrombogenic index.