The Core Issue: The Coumarin Compound
At the heart of the debate over whether cinnamon can be harmful is a naturally occurring compound called coumarin. Found in abundance in cassia cinnamon, coumarin is known to be hepatotoxic, meaning it can cause liver damage, especially when consumed in large doses over a prolonged period. The European Food Safety Authority (EFSA) has established a tolerable daily intake (TDI) of 0.1 mg of coumarin per kilogram of body weight. This threshold is easily exceeded with regular, high consumption of cassia cinnamon. In contrast, ceylon or "true" cinnamon contains only trace amounts of coumarin, making it the safer choice for consistent use.
Cassia vs. Ceylon: A Comparison
Understanding the key differences between the two main types of cinnamon is fundamental to consuming it safely. The cinnamon most people buy in North American grocery stores is cassia, valued for its low cost and strong flavor. Ceylon is often called "true cinnamon" and is less common and more expensive.
| Characteristic | Cassia Cinnamon | Ceylon Cinnamon |
|---|---|---|
| Coumarin Content | High (2,000–13,000 mg/kg) | Very Low (0.004–0.016 mg/kg) |
| Primary Risk | Liver damage with chronic high intake | Generally safe for daily consumption |
| Flavor | Strong, spicier, less sweet | Milder, sweeter, and more delicate |
| Appearance | Thick, dark reddish-brown sticks with a single, hard layer | Thin, light tan, paper-like layers that crumble easily |
| Availability | Widely available in most supermarkets | Found in specialty stores or online |
| Cost | Less expensive | More expensive |
Potential Side Effects of Excessive Cinnamon
Beyond the risk of liver damage, consuming too much cinnamon, particularly the high-coumarin cassia variety, can lead to several other health issues.
Liver Damage
As highlighted, the primary risk of excessive cinnamon consumption comes from coumarin. For individuals with pre-existing liver conditions, even smaller amounts can exacerbate issues. The effect is dose-dependent and typically reversible upon cessation of high intake, but continued exposure can lead to more serious complications.
Low Blood Sugar (Hypoglycemia)
Cinnamon is well-known for its ability to lower blood sugar levels, which can be beneficial for managing diabetes. However, in large doses, it can cause blood sugar to drop too low, especially for those already taking diabetes medication. This can lead to symptoms like dizziness, fatigue, and fainting. People with diabetes should consult a doctor before using cinnamon supplements.
Mouth Sores
Some individuals experience mouth sores, also known as cinnamon stomatitis, from consuming cinnamon flavoring agents in large amounts. This is an allergic reaction to cinnamaldehyde, a compound that gives cinnamon its distinct flavor. Symptoms can include soreness, swelling of the mouth or tongue, and white patches inside the mouth.
Breathing Problems
Inhaling large amounts of dry, ground cinnamon, as seen in the dangerous "cinnamon challenge," can be very hazardous. The fine texture of the powder can irritate the throat and lungs, potentially leading to choking, gagging, or even aspiration pneumonia, a serious condition caused by lung inflammation.
Medication Interactions
Cinnamon can interfere with certain medications, including blood thinners like warfarin and drugs for diabetes, heart conditions, or liver disease. Coumarin acts as a natural anticoagulant, and excessive cinnamon intake could amplify the effects of blood-thinning medications, increasing the risk of bleeding.
Safe Consumption Guidelines
To enjoy the flavor and potential benefits of cinnamon without the risks, follow these guidelines for safe consumption:
- Choose Ceylon over Cassia: For daily or frequent consumption, opt for Ceylon cinnamon due to its minimal coumarin content. If you are unsure, read the label, ask the manufacturer, or perform a simple visual check (Ceylon sticks are thinner and layer like paper).
- Moderation is Key: If using common cassia cinnamon, stick to very small amounts—ideally no more than half a teaspoon per day for a standard adult.
- Avoid Supplements: Do not take cinnamon supplements without consulting a healthcare professional. Supplements often contain concentrated, unlabelled cinnamon varieties with potentially dangerous coumarin levels.
- Never Attempt the "Cinnamon Challenge": This viral internet dare is extremely dangerous and can cause severe, life-threatening lung damage.
- Pregnant and Lactating Women: Given the limited research, pregnant or breastfeeding women should avoid consuming large medicinal amounts of cinnamon and stick to food-flavoring levels.
Conclusion
While cinnamon offers a delicious flavor and a range of potential health benefits, the risks associated with excessive consumption, particularly of the common cassia variety, are real and shouldn't be overlooked. The key to safe enjoyment is understanding the difference between cassia and ceylon cinnamon and practicing moderation, especially for those on medication or with specific health conditions. By making an informed choice, you can continue to enjoy this flavorful spice safely. Learn more about cinnamon from the National Center for Complementary and Integrative Health.
