The folate debate, and rewriting the radiocarbon curve

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Some 80 countries around the world add folic acid to their food supply to prevent birth defects that might happen because of a lack of the B vitamin—even among people too early in their pregnancies to know they are pregnant. This year, the United Kingdom decided to add the supplement to white flour. But it took almost 10 years of debate, and no countries in the European Union joined them in the change. Staff Writer Meredith Wadman joins host Sarah Crespi to discuss the ongoing folate debate.

Last year, a highly anticipated tool for dating ancient materials was released: a new updated radiocarbon calibration curve. The curve, which describes how much carbon-14 was in the atmosphere at different times in the past 55,000 years, is essential to figuring out the age of organic materials such as wood or leather. Sarah talks with Tim Heaton, senior lecturer in the School of Mathematics and Statistics at the University of Sheffield, and Edouard Bard, a professor at the College of France, about how the curve was redrawn and what it means, both for archaeology and for our understanding of the processes that create radiocarbon in the first place—like solar flares and Earth’s magnetic fields.

This week’s episode was produced with help from Podigy.

[Image: Andrew Shiva/Wikipedia; Music: Jeffrey Cook]

[Alt text: close-up photograph of layers in volcanic tephra]

Authors: Sarah Crespi; Meredith Wadman

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