All Essential Benefits/Effects/Facts & Information
This page on Cinnamon is currently marked as in-progress. We are still compiling research.
Cinnamon is popular spice worldwide. It exerts numerous biological effects on the body.
Cinnamon is frequently treated as an anti-diabetic compound, since it reduces the rate at which glucose enters the body. Not only does it help diabetics avoid blood sugar spikes, but it also improves glucose use in the cell itself.
Over time, cinnamon can reduce fasting blood glucose, and potentially cholesterol levels as well.
Cinnamon does not need to be purchased specifically as a supplement, and can be found in grocery stores. It does contain a liver toxin called coumarin, which can be harmful in high doses. Making cinnamon tea can reduce the risk of coumarin poisoning, since the toxin is left behind in the leftover sediment. Ceylon cinnamon, which is made from a different plant species, has lower levels of coumarin, which makes it a better supplement option.
1Cinnamon components and species
Cinnamon is a spice that contains several bioactive agents. Cinnamaldehydes give cinnamon its aroma, Coumarins (a toxin) contribute to taste, and several compounds including MethylHydroxyChalcone polymers (MHCPs) contribute to its systemic insulin sensitizing benefits. Beyond the three unique compounds listed, cinnamon also contains tannins, flavonoids, glycosides, terpenoids and anthraquinones.
2Cinnamon and blood sugar; anti-diabetic effects
Cinnamon exerts beneficial control effects against pro-diabetic diets in a number of ways.
Cinnamon can inhibit numerous digestive enzymes, such as alpha-glucosidase, sucrase and potentially pancreatic amylase (although the only results were confounded with acarbose). Via inhibition of these enzymes, cinnamon can decrease the influx of glucose into systemic circulation and avoid overly significant insulin spikes.
In systemic circulation (beyond the liver) cinnamon also possesses anti-diabetic effects. A compound in cinnamon, methylhydroxychalcone polymer (MHCP), acts as an insulin mimetic on adipocytes. MHCP's effects as an insulin mimetic are dose depend, and act by transphosphorlyating the insulin receptor on the cytoplasmic membrance (the same mechanism as the insulin molecule itself). Its effects on glucose uptake and glycogen, however dose-dependent, seem to be time-delayed (When insulin acts within 10 minutes of reaching the cell, MHCPs take 30-60, suggesting an intra-cellular time delay).
Cinnamon has also been implicating in aiding insulin function, potentiating its effects more than 20-fold in vitro.
When ingested in human trials, cinnamon shows much promise in reducing blood glucose levels and sometimes markers of lipid metabolism (LDL, Triglycerides, Total cholesterol). There are also intervention studies noting improved insulin sensitivity with cinnamon extract, possibly vicariously through the reduced blood glucose levels.
3Dosing and Coumarin avoidance
Coumarin is a hepatotoxic and carcinogenic phytochemical found in some plants, of which cinnamon is a high source of. It is not the active compound that reduces blood sugar, but one that exists alongside the active ingredient(s). It initially had a TDI (Tolerable Daily Intake) of 2mg/kg bodyweight max, but was lowered to 0.5 and currently stands at 0.1mg/kg bodyweight. Although a safety buffer is included in this last recommendation, some subsets of the human population seem more susceptible due to less of a capacity to metabolize it.
This is relevant since most anti-diabetic benefits come in a dose dependent manner, in the range of 300mg/kg bodyweight. In these doses, coumarin above the TDI can easily be ingested.
The best method of coumarin avoidance appears to be through the original source of cinnamon. Ceylon cinnamon has the lowest levels of coumarin with below 190mg/kg (some samples being below detection levels) whereas Cassia contains between 700 (at best) and 12,230mg/kg (at worst).. Ceylon can be detected in stick form via its numerous thin folds, whereas Cassia has less folds and a thicker appearance. They cannot be distinguished in powder form, and Cassia is more frequently used in production and manufacturing.
Via the above numbers, a 200lb human can ingest 4.78g of Ceylon Cinnamon and arrive at the 0.1mg/kg bodyweight TDI for coumarin at worst (using the highest recorded dose of coumarin in cinnamon). Using Cassia cinnamon with a coumarin will invariably place somebody above the TDI.
There seems to be little variance on coumarin absorption depending on form of cinnamon ingested. Similar serum levels and excreted levels were achieved with isolated coumarin, pill form cinnamon, tea and rice pudding (solid food). These results were standardized to X dose of coumarin, so source of cinnamon is irrelevant.
The above study, however, did note a 38.5% extraction rate of coumarin from powder to liquid when steeped (just boiling for 30 minutes); suggesting that one can tip the scales more in favor of water-soluble polyphenols and MHCPs relative to coumarins if steeped and served in tea or using said cinnamon water to mix protein shakes with, as the water-soluble components have a much higher extraction rate.