Biting research: Teeth provide clues into vitamin D’s roots
anthropologist Megan Brickley isn’t a dentist but she does know how to dig some interesting information out of teeth.
Brickley is part of a group of McMaster University researchers, working with colleagues in Quebec and France, who have developed a new way to determine vitamin D deficiencies from the dentine of ancient chompers.
Dentine is the material that forms the bulk of the tooth, and the methodology developed by the researchers can be used on teeth specimens hundreds of thousands of years old to get a sense of sun exposure experienced when the person lived.
It means a new diagnostic tool is available to scientists to examine countless teeth samples kept in museums around the world.
The technique makes use of the fact that new layers of dentine cannot mineralize if the person has suffered severe vitamin D deficiency, a disorder known as rickets. So layers can be examined to see levels of exposure to sunlight.
From this, researchers can gain insight into the adaptation by early humans who moved from equatorial Africa into regions that had less sunlight.
The dentine can be used to better understand skin pigmentation that was taking place to metabolize more sunlight.
“Anthropologists can get answers about some fairly impor tant questions such as changes in skin pigmentation and also questions about what is really happening in terms of changing levels of deficiency in societies,” said Brickley, who is known in Hamilton for her work examining the remains of soldiers from the Battle of Stoney Creek.
You’d think early humans would have been exposed to sun all the time, and you wouldn’t expect to find vitamin D deficiency with them — especially compared to humans who live in western societies today.
But Brickley says “humans are complex creatures and there is a range of social and cultural reasons why that might not happen.”
For example, she said, someone with a higher socioeconomic status who lived long ago might spend a lot of time indoors and wear clothing that shields from the sun.