Low GI Food of the Month

Cinnamon and cassia – don’t go barking up the wrong tree
Back in August 2006 we wrote about two promising studies reporting that as little as the equivalent of ¼ teaspoon of cinnamon daily may improve blood glucose control. Cinnamon is in the news again with a report in the June American Journal of Clinical Nutrition (Vol 85 No. 6) concluding that adding 6 grams (about a teaspoon) of cinnamon to 300 grams of rice pudding delays stomach emptying and reduces blood glucose levels. We wondered how feasible it is to eat 6 grams of cinnamon (that’s more than a teaspoon) at a sitting? ‘Perfectly feasible,’ says Ian Hemphill author of the Spice and Herb Bible (Spice Notes in Australia), ‘so long as it really is true cinnamon. I do it every morning stirring it into my porridge while it is cooking.’ But then he asked a curly question – had the researchers used true cinnamon in their study or was it cassia they were actually talking about!

Why? Well, true cinnamon (Cinnamomum zeylanicum Ceylon cinnamon) is easily and regularly confused with cassia (Chinese cassia C. cassia, Batavia cassia C. burmannii and Saigon cassia C. loureirii ). ‘Everybody is confused,’ says Ian ‘from consumers, to traders, processors and even the growers themselves. It is virtually impossible for the average consumer to tell the difference. In some countries it is illegal to sell cassia as cinnamon, but there’s very little policing, so it hardly has any effect. And the label won't help although the country of origin may give a clue. In the US for example, true or Ceylon cinnamon is almost unheard of, so anything called cinnamon is bound to be cassia, unless it’s Mexican cinnamon – this is because Mexico buys so much true cinnamon from Sri Lanka that the traders there have a grade of cinnamon called ‘Mexican’!


So, what’s the difference between 'true' cinnamon and 'cassia' cinnamon and does it matter? ‘For starters,’ says Ian, ‘the best cinnamon is a very thin underneath layer of bark from a quite young piece of branch, while cassia is the complete thickness of bark from the fully grown tree. And there are some significant differences in aroma and use. The aroma of cinnamon is delicate, sweet and subtle, and it's virtually impossible to use too much in your cooking. Cassia has a highly fragrant cinnamon aroma when it is ground, but you need to use moderation – too much cassia spoils the flavour and 6 grams in some dishes might be rather unpalatable.'

In addition, if people want to add ‘cinnamon’ to their cooking to help with blood glucose levels, then they need to be adding the one that's been tested. Cassia cinnamon was actually the spice (or supplement) used in the various studies published to date in Diabetes Care 26:3215-3218, 2003, the European Journal of Clinical Investigation Vol 36, No 5, and the latest one in the American Journal of Clinical Nutrition. Why? Well cassia has significant amounts (around 5%) of coumarin, while true cinnamon only has traces. If you want to know more about coumarin in cinnamon (and other foods for that matter), check out the fact sheet on Germany's Federal Institute for Risk Assessment (BfR) website: http://www.bfr.bund.de/cd/8487.

Meanwhile whether it’s true cinnamon in your spice rack or cassia cinnamon, 'they are both a great addition (in appropriate amounts) to smoothies, cakes, poached and stewed fruit for breakfast or a dessert, and for spicing up veggies such as pumpkin and zucchini (courgettes),' says Ian. For more ideas check out Herbies Spices: www.herbies.com.au