Cinnamon is said to be of significant help in controlling the blood glucose levels of type 2 diabetics. But just how effective is it and is it safe to use?
Cinnamon is a brownish highly-aromatic spice with a very distinctive flavour that is added to both sweet and savoury foods. The spice is actually the inner bark of cinnamon trees.
There are two main types of cinnamon: Ceylonese or ‘true’ cinnamon, and cassia cinnamon. Both types are obtained from related varieties of trees.
Both types of cinnamon are harvested by scraping off the trees’ outer bark and then prying off the inner bark. This inner bark consists of an outer wooden portion surrounding the strips of cinnamon.
The difference between the two types is that the wooden part is discarded when harvesting Ceylonese cinnamon, allowing this type of cinnamon to be rolled into stick-like quills that are then cut into finger-length sizes once dry.
When cassia cinnamon is produced the wooden part is retained. Cassia is not supple enough to be rolled into quills so it usually comes as pieces of thick woody bark.
Less than a third of the worldwide production of 35,000 tons a year consists of Ceylonese cinnamon.
Most of this type is produced in Sri Lanka though it is also grown in the Seychelles and Madagascar.
Indonesia produces about two-thirds of the global supply of cassia cinnamon, which is also produced in China, Vietnam and India.
Ceylonese v cassia cinnamon
Ceylonese cinnamon has a light-yellowish brown colour and a finer and more crumbly texture than cassia, which is medium to light reddish brown and is hard and woody in texture.
The flavour of true cinnamon is considered more aromatic and more subtle than the harsher taste of cassia cinnamon.
Ceylonese cinnamon quills consist of many thin layers and can be ground into powder easily in a spice or coffee grinder while cassia sticks are much harder. Indeed some sticks of cassia are so hard they can damage a domestic spice grinder and so this cinnamon is usually sold ready-ground.
It’s easy to see the difference distinguish between the two types of cinnamon when the barks are whole. However, once they have been ground into powder there is virtually no visual difference and they can only be distinguished by chemical analysis.
Being able to recognise the two varieties could be important for your liver as we’ll see below.
Use of cinnamon
Cinnamon is principally used as a condiment and added flavouring in cooking.
Its flavour is due to an essential oil that makes up 0.5% to 1% of its composition. This oil has a golden-yellow colour, an easily recognizable odour and a very hot aromatic taste.
In the Middle East, Persia and Turkey, cinnamon powder is added to a wide variety of sweet and savoury dishes.
In the USA, a cinnamon-sugar mix is used to flavour cereals, bread-based dishes (eg, cinnamon toast), and fruits (eg, cinnamon apple).
Cinnamon is also used in the making of chocolate and many desserts, such as apple pie, doughnuts, cinnamon buns, spicy candies, coffee, tea, hot cocoa and liqueurs.
Nutritional value of cinnamon
Ten grams (about 2.1 teaspoons) of ground cinnamon contain:
- Energy: 103.4 kJ (24.7 kcal)
- Fat: 0.12 grams (1.2%)
- Carbohydrates: 8.06g (80%) of which fibres: 5.31g (53.1%) and sugars: 0.2g (2%)
- Protein: 0.4g (4%)
All in all, it seems like cinnamon is good stuff.
Benefits of cinnamon
Cinnamon is used in traditional medicine to treat muscle spasms, vomiting, diarrhoea, infections, the common cold, loss of appetite, and erectile dysfunction.
Modern research indicates that this spice may indeed have some beneficial properties.
Researchers in Tel Aviv University have stated that an extract from cinnamon bark can inhibit the development of Alzheimer’s disease.
According to the National Institutes of Health in the USA, cinnamaldehyde (a chemical found in cassia) can help fight bacterial and fungal infections.
Studies on plants used in traditional Indian medicine have concluded that extracts from cassia are effective against HIV-1. Other studies have found that eugenol, a chemical found in cinnamon essential oils, inhibits the replication (in vitro ) of the virus that causes herpes.
And, according to a neurological scientist at Rush University Medical Center, cinnamon may help halt the destructive process of multiple sclerosis.
Though promising, most of these conclusions seem to be theoretical as they are based, as far as I could find out, on laboratory tests and have not been proved in replicable clinical trials using human subjects.
In addition, the big question for diabetics is: … can adding a daily dose of cinnamon to the diet help control blood glucose levels?
Diabetes and cinnamon
When I was first learning how to beat my diabetes, I discovered that you can use cinnamon to cheat on a blood glucose test for diabetes … in which you take a sugary drink to see how well your body keeps your glucose level under control. To blunt the glucose spike, all you have to do is to consume two teaspoons of cinnamon up to 12 hours before the test.
I researched the matter further and found that cinnamon can cut fasting glucose levels by up to 30%. So I began sprinkling it on my porridge (oatmeal) in the mornings.
Within a few days, my average glucose levels on awaking had dropped by nearly 0.5mmol/l (9mg/l) or about 8%, quite a bit short of 30%.
Nevertheless it was a significant drop, and it seems to me that this spice, in the form of ground powder you can buy from your local supermarket, can help you control your blood glucose levels.
I experimented with the quantity and found that a teaspoon a day seems to be needed to make a significant difference in blood sugar levels, while a half a teaspoon has little effect.
Later I discovered that several studies have shown that including cinnamon and cinnamon extract in the diet may help type to control blood glucose levels.
However a Cochrane review (a meta-analysis summarising and interpreting the results of medical research) published in 2012 found that cinnamon was no more effective than a placebo in reducing haemoglobin A1c (HbA1c), a long-term measurement of blood glucose control.
Despite the Cochrane review, there is still a consensus that cinnamon can help improve glucose levels for diabetics. But, according to a study published in Diabetics Care, for cinnamon to be effective you would have to consume up to six grams (about three teaspoons) of it a day.
However, ingesting large amounts of cinnamon on a daily basis could have an adverse effect on your liver. The problem is coumarin.
Coumarin is a natural perfume and flavouring found in many plants.
According to Germany’s Federal Institution for Risk Assessment (BfR), relatively low daily doses of coumarin can, over a few weeks, damage the liver of particularly sensitive individuals. This is not permanent damage and reverses once the persons affected stop taking coumarin.
The BfR has established a tolerable daily intake (TDI) of 0.1 milligram of coumarin per kilogram body weight per day. This amount can be consumed over a lifetime without posing a risk to health. There is no threat to health if it is exceeded for a short time.
The European Food Safety Authority recommends the same maximum daily intake of coumarin.
Coumarin occurs in high concentrations in cassia cinnamon and the BfR recommends that large amounts of this cinnamon should not be eaten. By comparison, Ceylonese cinnamon only contains low levels of coumarin which the BfR considers safe to eat.
But nearly all the studies done on the blood sugar effect of cinnamon were done on cassia cinnamon. Studies done on Ceylonese cinnamon do not show a blunting of the glucose spike when this cinnamon is ingested before a blood glucose test.
It may be that the active ingredient in cassia that blunts the sugar spike is coumarin.
It seems that if you take out the toxin, you also take out the benefit. This suggests that the wise thing to do would be to avoid taking cinnamon to reduce the glucose spike after meals.
Of course, you could stick to just using Ceylonese cinnamon, even though it seems to have little effect on your blood glucose levels. The problem is that it is almost impossible to distinguish between Ceylonese and cassia cinnamon in powder form.
In addition, the origin of the cinnamon is not normally declared on the packaging. As cassia is, quite legitimately, called cinnamon, you have no way of knowing whether you are taking Ceylonese or cassia cinnamon.
Give up cinnamon?
It seems that cinnamon can no longer be considered a safe and effective treatment for diabetes … if it’s safe (Ceylonese), it’s ineffective … if it’s effective (cassia), it’s not safe.
So, should I give up on my daily sprinkling (teaspoon) of cinnamon? My answer is No.
Cinnamon contains other benefits besides its ability to blunt spikes in sugar levels. It has potent anti-oxidant content … better than cloves and almost as good as purple cabbage.
As any damage to the liver from coumarin is reversible, I see no reason to give up mixing a sprinkling of cinnamon into my porridge (oatmeal) each morning. I have routine tests done on my liver function every nine months or so and my liver, so far, is doing fine.
Of course, as soon as any adverse affects are noticed I will eliminate cinnamon from my diet.
The best way to beat your diabetes, of course, is to reverse it by adopting and sticking to a healthy plant-based diet … with or without cinnamon.