Get Your Personalized Supplement StackSupplement Stack Quiz

Cinnamon (Cassia sp.)(bark)

Also known as: Cinnamomum cassia, Cassia cinnamon, Chinese cinnamon, cinnamon bark, Cinnamomum aromaticum

Overview

Cinnamon from *Cinnamomum cassia*, also known as Cassia cinnamon or Chinese cinnamon, is a spice derived from the dried bark of the Cassia tree. It is commonly used as a flavoring agent in culinary applications and as a traditional remedy, particularly for improving glycemic control and lipid profiles, especially in individuals with type 2 diabetes mellitus (T2DM). The key characteristics of Cassia cinnamon include its bioactive compounds such as cinnamaldehyde, cinnamic acid, and polyphenols. These compounds are hypothesized to exert antioxidant, anti-inflammatory, and insulin-sensitizing effects. Research on Cassia cinnamon is considered to be at a moderate maturity level, with multiple randomized controlled trials (RCTs) and meta-analyses available, although results can be inconsistent due to variations in study design and cinnamon preparations.

Benefits

Cassia cinnamon consumption has demonstrated significant reductions in fasting blood glucose (FBG) levels. Meta-analyses have reported FBG reductions of approximately −1.55 mmol/L in T2DM patients consuming cinnamon powder. Postprandial blood glucose area under the curve (AUC) has also been significantly lowered. Water extracts of cinnamon have shown smaller but still significant reductions in FBG. However, effects on HbA1c (glycosylated hemoglobin) are inconsistent across studies, with some meta-analyses finding no significant change. Improvements in lipid profiles (total cholesterol, LDL, HDL, triglycerides) are generally not statistically significant based on pooled analyses. Benefits appear more pronounced in adults with type 2 diabetes mellitus, with most studies focusing on this population. The reductions in fasting glucose are modest but potentially clinically relevant.

How it works

Cinnamon's polyphenols may enhance insulin receptor signaling and glucose uptake by cells, contributing to its potential benefits in glycemic control. Its antioxidant properties may reduce oxidative stress, which is implicated in insulin resistance. The primary biological pathways affected include insulin receptor kinase activity, glucose transporter (GLUT4) translocation, and inflammatory pathways. Active compounds like cinnamaldehyde are absorbed but undergo metabolism, with bioavailability varying by preparation form (powder vs. extract). Cinnamon primarily affects glucose metabolism and possibly lipid metabolism through modulation of insulin sensitivity.

Side effects

Cassia cinnamon is generally regarded as safe in typical dietary amounts, with supplementation at 1-2 g/day for up to 3 months being well-tolerated in clinical trials. Common side effects include mild gastrointestinal discomfort. Uncommon side effects include rare allergic reactions. Rare side effects include potential hepatotoxicity with very high doses due to coumarin content; caution is advised in individuals with liver disease. Drug interactions are possible with antidiabetic medications, potentially leading to hypoglycemia; monitoring is recommended. Contraindications include caution in pregnancy, liver disease, and bleeding disorders due to coumarin content. Limited data exists for children and pregnant women, and use is not recommended without medical supervision.

Dosage

A minimum effective dose of approximately 1 gram per day of Cassia cinnamon powder has shown effects on fasting glucose. Optimal dosage ranges are typically between 1-2 grams per day for up to 12 weeks, as used in many RCTs. The maximum safe dose is not well established, but caution is advised above 2-3 grams daily due to the risk of coumarin toxicity. Cinnamon can be taken with meals to potentially improve postprandial glucose levels. Ground bark powder and aqueous extracts have been studied, with powder form showing stronger evidence for glucose lowering. Bioavailability may be enhanced with food, although specific cofactors are not well defined.

FAQs

Is cinnamon effective for diabetes?

Evidence supports modest reductions in fasting glucose but inconsistent effects on HbA1c levels. It may be a helpful adjunct, but not a replacement for standard diabetes treatments.

Is Cassia cinnamon safe long-term?

Short-term use (up to 3 months) appears safe; long-term safety is unclear due to coumarin content. Monitor for any adverse effects and consult with a healthcare provider.

When should cinnamon be taken?

Typically, cinnamon is taken with meals to aid in glucose control. This can help to mitigate postprandial blood sugar spikes.

How soon will effects appear?

Benefits have been observed within 8-12 weeks in clinical trials, but individual responses may vary. Consistent use is important for observing potential effects.

Does cinnamon replace diabetes medication?

No, cinnamon is an adjunct and should not replace prescribed treatments. It can be used in conjunction with medication under medical supervision.

Research Sources

https://pubmed.ncbi.nlm.nih.gov/34408931/ – Mandal et al. (2021) conducted a systematic review and meta-analysis of multiple RCTs involving T2DM patients. The study found no significant reduction in HbA1c or lipid parameters, and inconsistent glucose lowering effects, highlighting the heterogeneity in cinnamon type, dose, and study design.
https://www.mdpi.com/2673-396X/6/1/3 – A 2023 systematic review and meta-analysis published by MDPI examined the effects of cinnamon on blood glucose parameters and BMI in T2DM and overweight subjects. The study reported modest improvements in blood glucose parameters and BMI, as well as improvements in inflammatory markers, but noted variability in cinnamon preparations and doses.
https://www.cureus.com/articles/63465-impact-of-cassia-bark-consumption-on-glucose-and-lipid-control-in-type-2-diabetes-an-updated-systematic-review-and-meta-analysis – This systematic review and meta-analysis investigated the impact of Cassia bark consumption on glucose and lipid control in type 2 diabetes. The review provides an updated analysis of the available evidence, focusing on the effects of Cassia cinnamon on relevant metabolic markers.
https://www.annfammed.org/content/11/5/452/tab-e-letters – This resource is an e-letter related to a publication in the Annals of Family Medicine. It provides additional context or commentary on the original research, potentially offering insights into the clinical implications of cinnamon supplementation.
https://synapse.koreamed.org/articles/1081520 – Lee et al. (2017) conducted a meta-analysis of 8 RCTs for cinnamon powder and 6 RCTs for water extract, involving adults with T2DM. The study found a significant reduction in fasting glucose (−1.55 mmol/L for powder) but no significant change in HbA1c, noting moderate heterogeneity for the powder form and low publication bias.