In the drought years 2018 and 2019, the median blood value of a vitamin D precursor was 10 nmol/liter higher than in the four previous years without extreme summer. This reduced the proportion of patients with poor vitamin D supply by 10 percent. This was shown by measurements from over 13,000 people whose vitamin D levels were determined in the central laboratory of the University Medicine Halle.
The research approach goes back to an attentive employee of the laboratory: “One day I noticed that the mean value of the vitamin D precursor had increased in 2018 compared to previous years. When the effect was also evident in 2019, we became curious,” explains study author Dr. Bernhard Kraus, clinical chemist of the laboratory. In the study, Kraus and his team collected vitamin D readings from six years and compared them with the actual hours of sunshine from the German Weather Service.
The vitamin D requirement is largely covered by the body’s own production in the skin. This requires UV-B radiation from sunlight, which in our latitudes is only sufficiently available from March to October.
If you want to know your values exactly, you have to have the concentration of the vitamin D precursor molecule in your blood determined. From a value below 50 nmol/liter, the supply is considered suboptimal, below 30 nmol/liter as deficient. Values that are too low can have a negative effect on bone health, among other things.
Which: DOI 10.1371/journal.pone.0242230