da Rosa MI, Beck WO, Colonetti T, et al. - Among 165 elderly people, researchers evaluated the connection of vitamin D and vitamin B12 with cognitive impairment. They obtained data from a cross-sectional study including people aged 80 years or older living in the urban and rural areas of the cities of Siderópolis and Treviso in the state of Santa Catarina, Brazil. From blood samples, vitamin D and vitamin B12 levels were measured. Using a Poisson regression model, crude and adjusted analyses of the link between vitamins D and B12 and cognitive decline were performed. According to the results, 35.2% showed cognitive decline. Even after adjustment for potential confounders, people aged ≥ 80 years with vitamin D levels of ≤ 18 ng mL−1 had a greater prevalence of cognitive decline. Furthermore, vitamin B12 levels of ≥ 496 pg mL−1 were also a risk factor for cognitive decline. A cross-sectional analysis does not allow a cause-effect connection to be inferred; further research is required to comprehend these interactions.