According to a new Duke University-led study, Increased intake of dietary calcium may be key to addressing widespread dental health problems faced by millions of rural residents in Ethiopia’s remote, poverty-stricken Main Rift Valley.

Most efforts to combat fluorosis in the region have focused primarily on treating drinking water to reduce its fluoride content.

The new Duke-led study, published online in the journal Environment International, finds that these efforts “may not be sufficient on their own, because of the region’s geology and the low threshold of exposure at which we found fluorosis was likely to occur,” said Avner Vengosh, professor of geochemistry and water quality at Duke’s Nicholas School of the Environment.