Taking large doses of cinnamon for long periods, or drinking a lot of cinnamon tea for a long time, can cause digestive upset. These can include common complaints like nausea, stomach pain, vomiting, and diarrhea. Cinnamon can also delay stomach emptying, which helps control blood sugar.

It's filled with antioxidants and offers several health benefits, including reduced inflammation and blood sugar levels, improved heart health, and perhaps even weight loss. Cinnamon tea may also fight off infections and reduce PMS and menstrual cramps.

In studies that found cinnamon had a positive effect on blood sugar levels, subjects ingested the equivalent of one teaspoon per day7—amounts small enough to easily work into a regular diet simply by sprinkling it on morning oatmeal, adding it to a chili recipe, or sipping it in tea.