The Hidden Dangers of Cinnamon

Cinnamon is touted as an herb that will help keep your blood sugar in control, relieve dyspeptic complaints like bloating and heartburn, help with symptoms of arthritis, stimulate appetite and fight inflammation. You’ll find it on grocery store shelves as a spice, in numerous self-care and processed food products and in supplement form. Cinnamon can have some adverse effects, though, so consult a doctor before using it therapeutically.

Coumarin Effects

Some cinnamon products have high coumarin content. This substance can cause liver damage, according to the Memorial Sloan-Kettering Cancer Center in New York. In food and supplement products, cassia cinnamon has much higher coumarin levels than Ceylon cinnamon. Coumarin also is suspected of triggering tumors based on information from animal studies, according to Germany’s Federal Institute for Risk Assessment.

Sensitivity

It’s possible to be sensitive to cinnamon products such as toothpaste and gum. If so, you may suffer inflammation in the gums, tongue, cheeks, lips or roof or floor of your mouth, note the July 2006 “Compendum of Continuing Education in Dentistry.” Your reaction to using such products may even lead to orofacial granulomatosis, according to an October 2007 study published in “Medicina Oral, Patología Oral y Cirugía Bucal.” This condition causes lesions and sometimes ulcers in your mouth, and may also cause enlarged lips and granulomas, or small areas of tissue inflammation. You also may suffer lymphedema, which is swelling caused by a blockage of your lymph system.

Drug Interactions

Using cinnamon raises your risk for hypoglycemia, or blood-sugar levels that fall too low, when it’s used with drugs used to treat diabetes such as acarbose, glipizide, insulin and miglitol, according to “The Essential Herb-Drug-Vitamin Interaction Guide,” by George T. Grossberg and Barry Fox. Your risk for hypoglycemia also increases when you use cinnamon with other supplements that lower blood-glucose levels including chromium, alpha-lipoic acid, psyllium, devil’s claw and Panax ginseng. Also use caution if you take blood-thinning medications because cinnamon may magnify your medicine’s effects due to its coumarin content. This raises risk for bleeding and bruising.

Other Considerations

Cinnamon has possible estrogenic activity, according to Memorial Sloan-Kettering Cancer Center. That means you need to consult a doctor and use it with caution if you have a hormone-sensitive condition. Also avoid medicinal doses of cinnamon when you are pregnant or nursing, advises Armando González Stuart of the University of Texas El Paso. If you have an ulcer, consuming large amounts of cinnamon may aggravate your condition. Also, never ingest cinnamon essential oil due to potential toxicity.