Executive Summary
Cinnamon is a spice used for 4000 years. It is anti–inflammatory and anti–oxidant.
A cinnamon variety called cassia is cheap, and available worldwide. It has few medicinal benefits, and also some side effects. A rare, and expensive, variety called ceylon cinnamon is medicinally valuable, with very low toxicity.
A toxic compound called coumarin reduces blood–clotting. So, you are advised to consume less than 0.5 g of cassia variety or 67 g of ceylon variety a day.
Cinnamon slows down carbohydrate digestion and stomach emptying. These help in lowering post–meal blood glucose.
Cinnamon also lowers insulin resistance and mimics some actions of insulin. These help in lowering fasting blood glucose.
Many trials have found benefits of cinnamon in lowering blood sugar by 10–30% in diabetic patients and lesser in normal people.
Read the full article for more discussion and medical references for the above.
Cinnamon is a spice used for at least 4,000 years of recorded history. Its health benefits, and toxicity aspects, are studied and well–known.
Cinnamon helps prevent many health problems. It is anti–inflammatory and anti–oxidant.
It also has been found to be useful in management of various medical conditions, such as insulin resistance, diabetes, heart disease, cancer, infections, inflammation, and neuro–degenerative diseases. Don’t worry; I will give you data and medical reference links on all these. This website will never claim anything, unless there is medical research proof.
Just keep in mind that you should not use cinnamon as the mainstay, or single therapy, for any of these conditions. Take it along with your regular medicines. Inform your doctor, if you are taking cinnamon.
Sources of cinnamon
Cinnamon is derived from the inner barks of several Cinnamomum tree species. Two of these varieties are cultivated for spice.
- Cinnamomum verus: This is also known as ceylon cinnamon, or ‘true’ cinnamon. It is expensive, rare, and medically most beneficial.
- Cinnamomum cassia: This is the most commonly used cinnamon in the world. It is cheap and medically far less beneficial. Unfortunately, a good bit of research on human beings has been done with this cassia variety (God knows why scientists don’t do some home work before they begin their trials).
Luckily, there is sufficient research done with ceylon cinnamon. So, we know the benefits of ‘true’ cinnamon.
Problems with cinnamon
I will take a slightly different route here. First, I will mention the problems and cautions about cinnamon.
Once we know the negative possibilities, we can evaluate the benefits better, in light of potential trouble. After all, it is fine to use anything, where the risk–to–reward ratio is highly favourable.
Coumarin
Coumarin is a compound found in cinnamon. It inhibits synthesis of vitamin K and so reduces blood–clotting. In fact, it is used in some anti–clotting medicines, such as Warfarin, which are used for preventing blood clots, deep vein thrombosis, and pulmonary embolism.
Coumarin gives cinnamon its blood–thinning properties. Small amount of cinnamon in food helps our blood stay slightly thinner. But, don’t mess with cinnamon by using it as an anti–coagulant, if you have a heart condition.
High concentrations of coumarin are known to cause liver and kidney damage. But, how much is too much?
Tolerable daily intake (TDI) of cinnamon
The European Food Safety Authority has advised a maximum recommended tolerable daily intake (TDI) of 0.1 mg of coumarin per kg of body weight. So, a typical 60 kg person should consume 6 mg of coumarin a day, maximum.
Ceylon cinnamon has 0.005–0.090 mg of coumarin per gram of cinnamon. So, a 60 kg person can consume up to 67 g of ceylon cinnamon a day.
Cassia cinnamon, the cheaper and commercially available version around the world, has 0.10–12.18 mg of coumarin per gram of cinnamon, which is nearly 250–1000 times more than that in ceylon cinnamon. So, you should not consume more than 0.5 g of cassia cinnamon a day.
The table below summarises the coumarin advisory for the two types of cinnamon.
| Cassia cinnamon | Ceylon cinnamon | |
|---|---|---|
| Coumarin per gram of cinnamon | 0.10–12.18 mg | 0.005–0.090 mg |
| TDI of cinnamon (60 kg person) | 0.5 g | 67 g |
A teaspoon of cinnamon powder contains about 2 gm of cinnamon. So, you should be fine with using ¼th teaspoon of cassia variety, or 32 teaspoons of ceylon variety, daily.
Most of the published research has been done using 1 to 6 gm of cinnamon, or ½ to 3 teaspoons of cinnamon powder a day. They better be using ceylon cinnamon on those poor patients!
Evaluating cinnamon trials
I advise a strong caution in analysing results of nutrient trials, as compared to the clinical trials of pharmaceuticals. They are altogether two different worlds, which most scientists do not consider.
Here is a detailed article I have written on this website about this: How to understand the evidence from the nutrients trials.
This is especially true for negative results. Negative does not refer to results that show problems (negative benefits). I am referring to negative results as those that do not show any effect or benefit of a nutrient. Results showing negative sides of nutrients, on the other hand, are equally vital and welcome.
Health benefits of cinnamon
Let us now look at the benefits of cinnamon.
Slowing down carbohydrate digestion
An enzyme in intestine, called α-Glucosidase, breaks down complex carbohydrates such as starch and poly–saccharides into glucose. If a nutrient can inhibit, or slow down, the action of α-Glucosidase, carbohydrate digestion will reduce, and blood sugar will not rise as much after a meal.
Another enzyme, called amylase, also helps break down complex carbohydrates in food into sugar. Your saliva makes some amylase, but your pancreas makes most of the amylase.
An article published in 2011 in the journal Nutrition and Medicine showed that cinnamon reduced carbohydrate digestion by inhibiting α-glucosidase in the small intestine.
An article published in 2010 in the journal Plant Foods for Human Nutrition showed that cinnamon reduces carbohydrate digestion by inhibiting the actions of intestinal α-glucosidase and pancreatic α-amylase.
Slowing down stomach emptying
Stomach emptying rate (GER) of food lowers post–meal blood sugar levels.
A paper published in 2007 in the American Journal of Clinical Nutrition showed that 6 g a day of cinnamon slowed down stomach emptying rate, and reduced post–meal blood sugar levels, without affecting the feeling of satiety.
Lowering insulin resistance
An article published in 2010 in the Journal of Diabetic Science and Technology showed that cinnamon reduced insulin resistance. It also showed benefits for blood glucose, blood lipids (fats), blood pressure, obesity, anti–oxidant status, and digestion.
An article published in 2008 in the Proceedings of the Nutrition Society attributed this benefit to chromium and polyphenols found in cinnamon.
Mimicking insulin action
Some compounds in cinnamon act like insulin in some, but not all, biochemical processes. As a result, they help an insulin–resistant body to utilise blood glucose better, thereby lowering blood sugar.
A paper published in 1998 in the journal Hormone Research showed that cinnamon inhibits a compound called TPT–1B (tyrosine phosphatase) that inactivates an insulin receptor. So, insulin receptors are able to function better.
Don’t get too worried with all this scientific stuff. I am just trying to impress you.:-) Actually, I am just trying to impress upon you that cinnamon has been studied in depth. we are not discussing fluff science here.
Controlling blood sugar
All the above points are good as long as cinnamon lowers blood sugar. So, does it?
Some research shows that cinnamon helps lower blood sugar levels by 10–30%. Some other research shows no benefit. No research has shown that cinnamon increases blood sugar. That is exactly what one should expect from nutrient research, as that article on this website mentioned earlier would have told you.
A study published in 2000 in the Agricultural Research Magazine showed that consuming 1 g of cinnamon per day can increase insulin sensitivity, and help manage or reverse type 2 diabetes.
A paper published in 2003 in the journal Diabetes Care showed that consuming 1, 3, or 6 g of cinnamon per day reduces serum glucose, triglyceride, LDL cholesterol, and total cholesterol in people with type 2 diabetes.
A 2006 paper in the European Journal of Clinical Investigation showed 10.3% lowering in fasting blood sugar with cinnamon compared to 3.4% lowering with a placebo.
An article published in 2007 in the journal Diabetes, Obesity, and Metabolism analysed five type 2 diabetic and 3 non-diabetic studies on cinnamon. This is called meta–analysis, which is analysis of analyses. Two diabetic studies showed 10–29% reduction in fasting blood glucose. One non–diabetic trial reported 8.4% fasting blood glucose reduction. Another non–diabetic trial showed good results in oral glucose tolerance test. Other studies showed no benefits.
A paper published in 2011 in the Journal of Medicinal Food compared the results of eight previous studies. They found an average 3–5% reduction in blood sugar levels.
A paper published in 2013 in the Journal of Traditional and Complementary Medicine showed that 1 g a day of cinnamon made no difference fasting blood sugar levels and HbA1c in patients with type II diabetes, after 1 and 2 months of cinnamon use. The study had 70 patients. They used cassia cinnamon, though.
Read on this website, a detailed article about pros and cons of the HbA1C test: Glycated hemoglogin: a test to measure long–term blood sugar control.
A paper published in 2013 in the journal Annals of Family Medicine did a meta–analysis of 10 different trials. It found that cinnamon can lower fasting blood glucose levels and increase insulin sensitivity. It also found that cinnamon lowered LDL–cholesterol and total cholesterol, increased HDL–cholesterol, and reduced blood triglycerides.
A paper published in 2016 study in the Journal of Intercultural Ethnopharmacology showed that in poorly controlled diabetics, 1 g of cinnamon for 12 weeks reduced fasting blood sugar by 17%.
A paper published in 2016 in the Journal of the Academy of Nutrition and Dietetics reviewed 11 studies of cinnamon and the treatment of diabetes. All of them showed a drop in fasting blood sugar levels. Studies that measured HbA1C levels, or long–term blood glucose control, showed modest reductions. Four of these studies achieved blood sugar reductions in line with the American Diabetes Association’s treatment goals, which is a big thing.
Cinnamon in other medical disorders
Cinnamon is also beneficial in heart problems, cancer, inflammation, infections, Alzheimer’s disease, and Parkinson’s disease.
The scope of this article is about cinnamon and sugar control. But, as promised, I will give you an authority web–link to an article that provides discussions and medical references about the claims above: Ten evidence–based health benefits of cinnamon.
First published on: 21st July, 2019
Image credit: Jennifer Birgl from Pixabay
Last updated on: 29th August 2022