For thousands of years—possibly even before it was used for flavor—people have held cinnamon in high regard for its medicinal value. Ancient Egyptians used it in embalming, and traditional medicine systems such as Ayurveda prescribed it for respiratory, digestive, and gynecological troubles.
In recent decades, many studies have found cinnamon can lower blood glucose levels in people with diabetes. While fewer studies have examined its metabolic impact on healthy people or people with prediabetes, growing evidence suggests benefits there as well, and researchers have identified multiple potential glucose-affecting mechanisms at work. In addition to its anti-diabetic qualities, cinnamon also shows other health benefits, including anti-inflammatory and antioxidant properties.
So if the idea of eating a little extra cinnamon tickles your taste buds, read on to learn about the effects of cinnamon and how to add it to your diet.
What is Cinnamon?
The spice we call “cinnamon” is made by grinding up the inner bark of evergreen trees from the genus Cinnamomum.
There are more than 250 known species of cinnamon trees. Still, most of the world’s cinnamon comes from two in particular: Cinnamomum cassia, sometimes called Cinnamomum aromaticum, and Cinnamomum verum, literally “true cinnamon,” also commonly known as Cinnamomum zeylanicum, or Ceylon cinnamon.
“Cinnamon seems to affect glucose in several ways, either by mimicking insulin or increasing its effectiveness.”
Cassia cinnamon, which accounts for most of the cinnamon in international trade, comes mostly from Indonesia and China. True or Ceylon cinnamon is native to Sri Lanka (formerly Ceylon, hence the name). By the time the Europeans found Ceylon cinnamon trees growing in the island nation, people in India were well-accustomed to cooking and healing with cassia cinnamon, which they still call dalchini in Hindi—possibly from the Sanskrit for “Chinese wood.”
Cassia tends to have a more pungent taste and coarser texture, but this may be difficult to discern unless you’re testing the two varieties side-by-side. The best way to know which type you’re buying is to check the label. Ceylon cinnamon will be identified as such; cassia cinnamon may just be called “cinnamon.” Cassia is more common, particularly in North America, since it’s cheaper to produce.
How Does Cinnamon Affect Blood Sugar?
Cinnamon seems to affect glucose in several ways, either by mimicking insulin or increasing its effectiveness. Researchers have isolated several chemical compounds that may have different, and perhaps complementary, effects.
- One highly studied mechanism is a chemical in cinnamon called methyl hydroxychalcone polymer, or MHCP. MHCP essentially mimics insulin, giving it an assist in blunting blood sugar spikes by stimulating glucose oxidation—essentially, enabling glucose to be absorbed into cells from the blood and used as energy. In addition to the higher glucose uptake, MHCP also increased glycogen production. One study found that MCHP works synergistically with insulin, meaning that their combined effect is greater than the sum of their individual effects. Other research suggests that additional compounds in cinnamon besides MHCP, such as certain phenolic acids, may also increase insulin receptor signaling.
- In addition to the insulin-like effects, cinnamon may also slow digestion, helping reduce blood glucose levels. A study of 14 healthy subjects found that six grams of cinnamon, mixed in with a meal of 300 grams of rice pudding, delayed gastric emptying—the movement of food out of the stomach and into the small intestine, where glucose is absorbed. It also reduced post-meal blood sugar levels from 30 minutes until at least two hours after eating. While both effects were significant, the reduction of blood glucose after eating was more pronounced, suggesting to the researchers that the gastric emptying worked in concert with the insulin receptor triggering. However, a later study—which looked at nine subjects who took three grams of cinnamon—found that these effects did not carry over to high-fat, rather than high-carb meals.
- Other compounds in cinnamon may also play a role in its metabolic effects. Animal studies have found that cinnamaldehyde, the compound that gives cinnamon its distinct flavor and odor, is active at multiple levels of the insulin-signaling pathway, increasing insulin sensitivity, and improving the ability of cells to absorb glucose. Cinnamon bark extract may also lower post-meal blood glucose by inhibiting certain intestinal and pancreatic enzymes, slowing the rate of carbohydrate digestion.
- Other research shows cinnamon may have positive effects beyond glucose control. A study of 60 people with Type 2 diabetes found that cinnamon also reduced triglycerides, LDL cholesterol, and total cholesterol, all risk factors associated with metabolic syndrome and cardiovascular disease.
How Can I Incorporate Cinnamon Into My Diet?
There’s no official recommended dose of cinnamon for healthy people who want to take advantage of its benefits. However, most of the existing research has found effects at doses between one and six grams. This lines up with the 2003 USDA study mentioned earlier, which found benefits of taking even just half a teaspoon, or a little more than a gram.
Here are our three favorite ways to incorporate cinnamon into meals:
- Add 1-2 teaspoons to a smoothie
- Put it in your coffee. Don’t just dump a big spoonful in your joe or you could end up with a sludgy mess. Here are tips for incorporating cinnamon into your coffee. And here’s a recipe for a cinnamon coconut latte made with cinnamon and slow-digesting fat (found in the coconut milk).
- Add it to a rub for meat or tofu. Cinnamon is one of the spices in Chinese Five Spice, a great addition to veggie or tofu dishes. If you eat meat, add cinnamon to your rub.
If you’re not a fan of the taste, taking cinnamon supplements might be a viable option. Although researchers haven’t compared the effects of raw cinnamon and cinnamon capsules, both have been used in studies and produced similar outcomes.
Are There Any Risks to Eating Cinnamon?
All cinnamon contains a compound called coumarin—higher in cassia than ceylon. Coumarin can cause liver damage and tumors in animals at high doses. The risk to humans is primarily in people with existing liver damage, and even then when ingesting far higher amounts than you would typically get in your diet.
If you’re upping your cinnamon intake, it’s best to start small and build up to larger amounts gradually. You may find that too much cinnamon irritates your digestive system, or you could have an allergy that doesn’t present itself in lower quantities. That allergy, though rare, could lead to uncomfortable symptoms such as swelling, burning, itchiness of the mouth, or mouth sores.
Since cinnamon lowers blood sugar, you may want to avoid taking extra cinnamon if you are already at risk for low blood sugar (hypoglycemia). Coumarin is also a natural blood thinner, so you may want to avoid it if you’re already taking blood thinners, such as warfarin or statins.
It’s also unknown whether taking extra cinnamon has any side effects during pregnancy or breastfeeding, so it may be best to err on the side of caution.