Human hair can now be used to measure vitamin D levels

Aoibhín Bryant

Over one billion people are estimated to be affected by vitamin D deficiency, which has been associated with poor bone health.

Levelsof vitamin D can now be measured using hair samples, a research study from Trinity College and St. James’ Hospital has found.

A study has discovered that months of vitamin D levels can be tested for in samples of hair, providing an alternative to blood tests.

Lina Zgaga, an Associate Professor at TCD and lead author of the study, says that this can lead to an improved diagnosis of vitamin D deficiency.

“The test based on the hair sample might be able to give doctors a measure of vitamin D status over time – if hair is long enough, this even might be over a few years”.

Currently, the best way to test for vitamin D levels is through blood tests. This can be uncomfortable for the patient and requires a professional to conduct the tests. Furthermore, blood tests can only measure the vitamin D levels at that certain time.

This can raise problems as people are more likely to have sufficient vitamin D levels in the summertime when the weather is better but not reach adequate levels in the winter.

Co-author and principal biochemist at St. James’ Hospital, Dr. Martin Healey, says that this new research is not only useful for vitamin D diagnosis but also for vitamin D maintenance.

“Having a knowledge of an individual’s long-term vitamin D status through analysis of hair samples may allow for better strategies to maintain stable and adequate vitamin D concentrations over an extended period,” he said.

Over one billion people are estimated to be affected by vitamin D deficiency, which has been associated with poor bone health. A lack of vitamin D could also be a factor for depression, diabetes, cardiovascular disease, cancer and inflammation.

“Further research is needed to establish the exact relationship between vitamin D concentration in the blood and in hair over time,” said Zgaga. “We also need to investigate different factors that might affect vitamin D levels in hair, the most obvious ones being hair colour and thickness, or use of hair products such as hair dye.”

This new research can also be applied to analyse people and mammals from the past, according to Dr. Eamon Laird, nutrition research fellow at TCD and co-author.

“Hair, along with teeth, are some of the longest lasting surviving biological materials after death and thus it could be possible to for the first time assess the vitamin D status of historical populations,” he said.


Aoibhín Bryant

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