Dear Dietitian,

My boyfriend is a big believer in taking dietary supplements. He has type 2 diabetes, and he takes medication for this. He eats right most of the time and exercises three times a week. He recently started taking cinnamon to help improve his blood sugar levels. Does cinnamon really help with blood sugar?

Sharon

Dear Sharon,

It sounds like your boyfriend is exercising good judgment in his diabetes management. It also sounds like he has a kind, supportive girlfriend. Type 2 diabetes is very manageable, but it requires exercise, monitoring blood glucose levels, a healthy diet, and sometimes medication. Many people may include an integrative approach to diabetes management. One such approach includes cinnamon.

In 2018, 34.2 million Americans, or 10.5% of the population, had diabetes (1). About 1.5 million new cases of diabetes are diagnosed every year in the US. In type 2 diabetes, the pancreas still secretes insulin, but it may not produce enough, or the body cannot use the insulin efficiently. In contrast, in type 1 diabetes, the pancreas' beta cells have been damaged and can no longer secrete insulin.

Cinnamon comes from the Greek, meaning "sweet wood." It is a spice found in just about every kitchen cabinet in America and is created from the Cinnamomum tree's inner bark. There are two main types of cinnamon: Ceylon cinnamon and cassia. Cassia is most likely the type of cinnamon in your spice rack, as it is the most common type sold in the US. Cassia cinnamon contains coumarin, which may cause liver damage when taken in high doses. If you plan to take a supplement, Ceylon cinnamon would be the wiser choice. 

The manner in which cinnamon may help lower blood sugar levels is unclear. Scientists believe the spice helps in two ways. Cinnamon may play a role in transporting glucose into the cell where it belongs, thereby lowering the amount of glucose in the bloodstream. Cinnamon may also improve insulin sensitivity, which is how well your body responds to insulin. In other words, does your body allow insulin to perform its duty?

Several small studies on cinnamon's effect on blood sugar levels have produced mixed results. Different types of cinnamon are used in studies, and doses are variable, which makes it difficult to compare results. In a meta-analysis of sixteen randomized controlled trials, cinnamon significantly reduced fasting blood sugar levels and reduced insulin resistance. Interestingly, it did not reduce hemoglobin A1C levels, the three-month average blood sugar level (2). However, other studies have found that cinnamon lowered both fasting blood sugar and A1C.

The American Diabetes Association does not recommend using cinnamon to help control blood sugar levels, stating there is not enough evidence to show that it is effective (3). It is important to remember that diabetes management involves more than just one approach. It requires a healthy lifestyle. Talk to your doctor before deciding to use cinnamon as a part of your diabetes treatment regimen.

Until next time, be healthy!

Dear Dietitian

References

1. Type 2 Diabetes (2019 May 30) https://www.cdc.gov/diabetes/basics/type2.html
2. Deyno S, Eneyew K, Seyfe S, Tuyiringire N, Peter EL, Muluye RA, Tolo CU, Ogwang PE. Efficacy and safety of cinnamon in type 2 diabetes mellitus and pre-diabetes patients: A meta-analysis and meta-regression. Diabetes Res Clin Pract. 2019 Oct;156:107815. doi: 10.1016/j.diabres.2019.107815. Epub 2019 Aug 16. PMID: 31425768.
3. McCulloch, M. Herbs and Spices: Cinnamon's Link to Diabetes Control. Today's Dietitian

2015 Nov; 17(11): 12.