Sensitive people who consume cinnamon-flavored foods, drinks and food supplements may have a higher risk of liver damage, researchers from the University of Mississippi, USA, and King Saud University, Riyadh, Saudi Arabia, report in the Journal of Agriculture and Food Chemistry.

Cinnamon is one of the most important flavoring agents in foods and drinks, team leader Ikhlas Khan explained. It is the second most popular spice, next to black pepper, in the United States and Europe.

Ceylon cinnamon, also known as “true cinnamon” (cinnamon verum) is very expensive. Therefore, most foods in the USA and Western Europe, including sticky buns, breads and other products use the cheaper Cassia cinnamon (dried Cassia bark).

Canelle Cinnamomum verum Luc Viatour crop1
Cinammon sticks and ground cinnamon

Cinnamon comes from the bark of trees and is sold as sticks or powder in the country of origin. Ceylon cinnamon grows in Sri Lanka, Madagascar and the Seychelles, while Cassia cinnamon comes from Indonesia and China. Previous studies have linked coumarin intake to liver damage in a small number of sensitive individuals.

True cinnamon has very little coumarin, unlike Cassia cinnamon. A 2010 German study found that on average, Cassia cinnamon powder had up to 63 times more coumarin compared to Ceylon cinnamon powder, while Cassia cinnamon sticks contained 18 times more than Ceylon cinnamon sticks.

The researchers in this latest study also reported that coumarin, a naturally-occurring substance, may cause liver damage in some sensitive people.

Cinnamomum Verum vs Cinnamomum Burmannii
Ceylan cinnamon (left) has much less coumarin than Cassia cinnamon (right)

The authors wrote:

“As found in this study, coumarin was present, sometimes in substantial amounts, in cinnamon-based food supplements and cinnamon-flavored foods.”

According to health officials, consumers cannot tell the difference between Ceylon and Cassia cinnamon in powder form. Cinnamon sticks look different though – Cassia cinnamon sticks consist of a thick layer of rolled bark, while Ceylon cinnamon sticks have thin layers.

Written by Christian Nordqvist