ODIN project provided the evidence to prevent vitamin D deficiency in Europe and improve nutrition and public health through food. By establishing an internationally standardized analytical platform for 25OHD, ODIN measured the distribution of circulating 25OHD and describe the prevalence of vitamin D deficiency in Europe. Using available biobanks and databases from National nutrition surveys ODIN delineated the relative contributions of sun and dietary sources of vitamin D to circulating 25OHD. In support of vitamin D recommendations, ODIN carried out three RCT in pregnant women, children and teenagers and a fourth RCT in ethnic immigrant groups to provide experimental data to specify vitamin D intake requirements.