Clue to your vitamin D levels in hair strands

VITAMIN D has been measured in hair for the first time, in a study at Trinity College Dublin. Until now, the vitamin has only been measured using blood samples.

More than one billion people are deficient in vitamin D, which has been linked with bone health, depression, cardiovascular disease and inflammation.

Writing in the journal Nutrients, the researchers say that while blood analysis captures vitamin concentration at a moment in time, hair — which grows about 1cm a month — reflects seasonal changes over months or years, helping doctors stabilise patients’ vitamin levels long term.