Summary of Cinnamon Research

Coumarin Toxicity and Cinnamon

Coumarin, found in cassia cinnamon, may have toxic effects on the liver and could be carcinogenic. A tolerable daily intake (TDI) for coumarin is set at 0.1 mg/kg body weight. Heavy consumers of cassia cinnamon, especially during festive seasons, may reach this TDI limit.

Cinnamon as an Insulin Mimic

Research has shown that methylhydroxychalcone polymer (MHCP) from cinnamon can mimic insulin's actions in fat cells, potentially aiding in managing insulin resistance and glucose metabolism pathways.

Cinnamon and Blood Sugar Regulation

Cinnamon extracts can inhibit enzymes like α-glucosidase and α-amylase, helping to manage post-meal blood sugar levels in diabetic patients. Cinnamon's efficacy in reducing blood glucose has been observed in both in vitro and in vivo experiments.

Comparative Studies on Cinnamon Species

Different species of cinnamon bark have varying effectiveness in inhibiting carbohydrate-digesting enzymes. Thai cinnamon and Ceylon cinnamon have shown significant inhibitory effects, suggesting their potential in controlling blood sugar levels after meals.

Insulin Function Enhancement by Cinnamon

Cinnamon compounds can enhance insulin function by stimulating the insulin receptor and inhibiting enzymes that deactivate it. This suggests cinnamon's potential use in insulin resistance research related to type 2 diabetes.

Cinnamon's Effect on Diabetic Patients

Studies have provided mixed results on cinnamon's ability to lower blood glucose levels in type 2 diabetes patients. While some studies show significant reductions, others do not, highlighting the need for further research.

Coumarin Bioavailability in Cinnamon

A study concluded that coumarin from cinnamon is nearly as bioavailable as isolated coumarin, implying that TDI for isolated coumarin can be applied to cinnamon-containing foods.

Conclusion

Although cinnamon has been traditionally used for its antidiabetic properties and studies have shown it can reduce blood sugar levels, the consistency of these effects varies. Cinnamon also contains coumarin, which can be harmful at high levels. Further research is needed to fully understand the health benefits and risks of cinnamon consumption.

References:

1. Toxicology and risk assessment of coumarin: focus on human data
2. A hydroxychalcone derived from cinnamon functions as a mimetic for insulin in 3T3-L1 adipocytes
3. Cinnamon extract inhibits α-glucosidase activity and dampens postprandial glucose excursion in diabetic rats
4. Inhibitory activity of cinnamon bark species and their combination effect with acarbose against intestinal α-glucosidase and pancreatic α-amylase
5. Regulation of PTP-1 and insulin receptor kinase by fractions from cinnamon: implications for cinnamon regulation of insulin signalling
6. Insulin-like biological activity of culinary and medicinal plant aqueous extracts in vitro
7. The potential of cinnamon to reduce blood glucose levels in patients with type 2 diabetes and insulin resistance
8. Cinnamon supplementation in patients with type 2 diabetes mellitus
9. Effects of a cinnamon extract on plasma glucose, HbA, and serum lipids in diabetes mellitus type 2
10. Cinnamon improves glucose and lipids of people with type 2 diabetes
11. Chromium and polyphenols from cinnamon improve insulin sensitivity
12. Cinnamon: potential role in the prevention of insulin resistance, metabolic syndrome, and type 2 diabetes
13. Quantification of flavoring constituents in cinnamon: high variation of coumarin in cassia bark from the German retail market and in authentic samples from indonesia
14. Relative bioavailability of coumarin from cinnamon and cinnamon-containing foods compared to isolated coumarin: a four-way crossover study in human volunteers