Many people suffer from vitamin D deficiency, which as well as causing brittle bones can lead to an increased risk of respiratory diseases Exposing poultry to UV light boosts vitamin D content in eggs and can help people suffering from brittle bones. The new study aimed to test the practical feasibility of the method and was conducted on two holdings with comparisons made between two different chicken breeds (Lohmann Selected Leghorn hens and Lohmann Brown hens), assorted lamps and different durations of light exposure per day. Results The results showed that after only three weeks of UV light exposure for six hours per day, the vitamin D content of the eggs increased by 3.7-fold in eggs from the Lohmann Selected Leghorn hens and 4.2-fold in the Lohmann Brown hens. This value did not rise any further in the following weeks. The additional UV light did not cause any problems for the hens – they neither avoided the area around the lamps nor did they act differently. As a result, researchers conclude that their method also works under practical conditions and this could represent an important step forward towards supplying the population with vitamin D. • The study, “Feasibility of artificial light regimes to increases the vitamin D content in indoor-laid eggs,” was supported by the Competence Cluster for Nutrition and Cardiovascular Health, and funded by the Federal Ministry of Education and Research. It was published in Poultry Science