Vitamin D status and its associations with disease over the course of adulthood – a Northern Finland Birth Cohort 1966 study

This doctoral study examined the changes in vitamin D status among the Northern Finland Birth Cohort 1966 population and highlights the improvement in vitamin D status. Still, one individual out of four had low vitamin D status [serum 25(OH)D]. The results of this doctoral study also bring additional information about the associations of vitamin D status and chronic conditions among population with sufficient mean vitamin D status.

This study utilizes data from the Northern Finland Birth Cohort 1966. Among the sample from the 31-year follow-up study, we found no significant difference in vitamin D status between participants with depression, schizophrenia, other psychoses, and controls.

The second study demonstrated an improvement in vitamin D status following the start of vitamin D food fortification in Finland. This improvement was also observed as a decrease in the seasonal variation in vitamin D status and as the highest increase in vitamin D status among those with the lowest vitamin D status at baseline.

In the third study, we found that, by the age of 54 years, one out of ten of the cohort participants had multimorbidity measured by the Charlson Comorbidity Index. Vitamin D status at 46 years predicted multimorbidity at 54 years, but the association was attenuating when adjusting for body mass index.