How Do Vitamin D Levels Change Through the Seasons? - Chromatography Investigates

Vitamin D deficiency has been a topic of health professional and media debate over the past few years - with low vitamin D becoming a cause for concern, especially for at risk groups like the young and elderly. Although vitamin D concentrations are seen by most researchers to be essential for bone health, there is a discussion regarding the correlation between vitamin D concentrations and certain disease risks.

The main source, and most important source, of vitamin is from a reaction that that takes place in the skin in response to us absorbing sunlight. Much effort has been made in recent years to try and get people to go outdoors to raise vitamin D levels. But, in some countries, including the UK, their position on the Earth’s surface makes it extremely difficult to get enough sunlight all year round to produce enough vitamin D for our optimal needs.

A solar study in Denmark

A recent paper published in the journal Nutrients has looked at vitamin D concentration in adults and children in Denmark - another country where latitude restricts the quantity of sunlight available to produce vitamin D. The study also investigated the seasonal variations seen in adults and children. The main method used to analyse vitamin D levels in the body is to use chromatography - the future of this key analytical technique is discussed in this article, The Evolution of Ultra High-Performance Liquid Chromatography: Expanding the Future of Separation Technologies.

Recommendations exist to supplement the diet of certain groups with supplements to make sure they have sufficient vitamin D in their diets to overcome the lack of natural vitamin D from sunlight. However, due to a lack of data, it is difficult to formulate recommendations for different groups and to see the effect that different seasons have on vitamin D levels.

Seasonal variation in vitamin D

The aim of the study reported in Nutrients - Vitamin D Status and Seasonal Variation among Danish Children and Adults: A Descriptive Study - sampled adults and children aged 2-69 years from three regions and in both spring and autumn. The study participants did not take any vitamin D supplements during the study period.

The tests were conducted on serum samples taken from each participant and analysed using liquid chromatography - tandem mass spectrometry. The analysis found that there was a seasonal variation in the levels of vitamin D in both adults and children. The study concluded that most participants were vitamin D sufficient in autumn, but there was also a significant portion who were vitamin D insufficient in spring. The team also reported that there might be a significant genetic factor that could play a role in vitamin D levels in humans.