Cinnamon is a widely used spice known for its flavor and potential health benefits, but not all cinnamon is created equal. The most common type, Cassia cinnamon, contains significant levels of a natural compound called coumarin, which can be harmful to the liver and interact with certain medications when consumed in large amounts. Ceylon, or "true" cinnamon, contains only trace amounts of coumarin and is a safer choice for frequent consumption.
This distinction is vital for understanding who should not take cinnamon or should limit their intake. For most healthy adults, small amounts of Cassia cinnamon used in cooking are generally safe. However, the risks increase when consuming supplements, larger quantities, or for individuals with specific health conditions or medication regimens.
The difference between Cassia and Ceylon cinnamon
Understanding the type of cinnamon is the most important factor in assessing risk. The differences are not only in their taste and origin but, most importantly, in their chemical composition, particularly the coumarin content.
- Cassia cinnamon (Cinnamomum cassia): This is the most common and inexpensive type found in grocery stores in North America. It is often thicker, with a more pungent, stronger flavor. Cassia cinnamon contains a significant amount of coumarin, with levels potentially ranging from 1% to 5% or even higher.
- Ceylon cinnamon (Cinnamomum verum): Also known as "true cinnamon," Ceylon is native to Sri Lanka and has a milder, sweeter, and more delicate flavor. It contains very low levels of coumarin, typically ranging from 0.004% to 0.02%. This makes it a much safer option for those who consume cinnamon regularly or in larger doses.
Who should avoid or limit cinnamon intake?
Individuals with liver disease
Because the liver is responsible for metabolizing coumarin, individuals with pre-existing liver conditions, such as hepatitis or fatty liver disease, should avoid consuming Cassia cinnamon, especially in high doses or supplement form. Even smaller amounts could pose a risk, as their liver's ability to process the compound is already compromised. Case reports have even linked cinnamon supplements to acute hepatitis in people also taking statins, a medication metabolized by the liver.
People taking specific medications
Cinnamon can interact with several types of prescription drugs, altering their effectiveness or intensifying side effects.
- Diabetes Medications: Cinnamon may lower blood sugar levels. Combining cinnamon supplements with diabetes drugs like insulin, metformin, or sulfonylureas could cause blood sugar to drop too low, leading to hypoglycemia.
- Blood Thinners (Anticoagulants): The high coumarin content in Cassia cinnamon has blood-thinning properties. Taking it alongside medications like warfarin (Coumadin) can significantly increase the risk of bleeding or hemorrhage.
- Liver-Metabolized Drugs: Cinnamon can affect the liver enzymes responsible for breaking down certain medications, including some statins, anti-seizure drugs, and even acetaminophen (Tylenol). This can increase the risk of liver damage.
- Blood Pressure Drugs: Cinnamon can have a mild blood pressure-lowering effect. When combined with antihypertensive medications, it could cause blood pressure to fall excessively low.
Pregnant and breastfeeding women
While typical culinary amounts of cinnamon are considered safe during pregnancy and breastfeeding, high doses, such as those found in supplements, are not recommended. There is insufficient research on the safety of large medicinal quantities in these populations. The potential risks associated with coumarin from Cassia cinnamon make Ceylon a safer choice if higher intake is desired, but consulting a doctor is always prudent.
Those with cinnamon allergies
Although rare, some individuals have an allergic reaction to cinnamon or its components, such as cinnamaldehyde. Allergic responses can range from mild mouth sores (cinnamon stomatitis), itching, or skin irritation to more severe symptoms like digestive upset, wheezing, or difficulty breathing. In rare cases, a severe reaction called anaphylaxis is possible.
Before and after surgery
Cinnamon can affect both blood sugar levels and blood coagulation. For this reason, medical experts recommend that patients stop taking cinnamon supplements at least two weeks before any scheduled surgery. This helps prevent complications with blood sugar control and excessive bleeding during or after the procedure.
Infants and young children
Children have a lower body weight, which means they can exceed the tolerable daily intake of coumarin from Cassia cinnamon much more quickly than adults. Their developing livers may also be more vulnerable. Limiting their intake of Cassia cinnamon and opting for Ceylon is a safer approach.
People with gastroparesis
Some research suggests that cinnamon can delay gastric emptying, a process already slowed in people with gastroparesis. Therefore, these individuals may want to limit their cinnamon consumption to avoid worsening their condition.
Cassia vs. Ceylon Cinnamon: A comparison table
| Feature | Cassia Cinnamon | Ceylon Cinnamon |
|---|---|---|
| Common Name | Standard or regular cinnamon | True cinnamon, Sri Lankan cinnamon |
| Coumarin Content | High (1%-5% or more) | Very Low (0.004%-0.02%) |
| Flavor | Stronger, more pungent, slightly spicy | Milder, sweeter, more delicate |
| Appearance | Thick, single, tight roll of bark | Thin, multiple layers of rolled bark |
| Primary Risk | Potential liver toxicity with excessive intake | Minimal risk; generally considered very safe |
| Price | Less expensive and widely available | More expensive and found in specialty stores |
How to reduce your risk
For most people, using cinnamon to flavor food in moderate amounts is safe. However, those in the at-risk groups mentioned above should take precautions.
- Use Ceylon Cinnamon: If you frequently consume large quantities of cinnamon or use supplements, switching to Ceylon cinnamon is the safest option due to its negligible coumarin content.
- Practice Moderation with Cassia: Limit daily intake of Cassia cinnamon to a small sprinkle, especially for those who bake often or add it to multiple daily meals or beverages. The tolerable daily intake (TDI) for coumarin is low, and one teaspoon of Cassia can exceed it for some adults.
- Consult a Healthcare Provider: Always talk to your doctor or pharmacist before starting cinnamon supplements or significantly increasing your intake, particularly if you have a pre-existing medical condition or take prescription medications.
Conclusion: Informed choices for safe consumption
While cinnamon offers many benefits as a natural anti-inflammatory, antioxidant, and blood sugar regulator, it is not without risks for certain individuals and medication regimens. The key takeaway is to be aware of the type of cinnamon being consumed—Cassia, with its high coumarin levels, should be used sparingly, if at all, by at-risk groups. Ceylon cinnamon offers a much safer alternative. By understanding the potential interactions and risks, consumers can make informed choices to enjoy the benefits of this popular spice safely.
National Center for Complementary and Integrative Health (NCCIH)
