Diabetes is a condition marked by abnormally high blood sugar levels. If it is not appropriately managed, it can result in heart disease, kidney disease, and nerve damage .
While anti-diabetic medications and insulin injections are frequently used to treat diabetes, many people are also interested in foods that can help lower blood sugar.
Cinnamon is one such spice that is frequently used in both sweet and savory dishes worldwide. It offers a plethora of health benefits, including the ability to lower blood glucose levels and aid in diabetes management.
Let’s explore cinnamon’s effects on blood sugar control and diabetes and whether cinnamon can reverse diabetes.
What is Cinnamon?
Cinnamon is a spice made from the inner bark of several Cinnamomum tree species. In addition to its culinary uses, cinnamon has been used in traditional medicine and food preservation for thousands of years.
The dried bark curls into cinnamon sticks or quills, which can be ground into cinnamon powder. Many cinnamon varieties are sold in the US, and they are typically divided into two categories:
- Ceylon: Also known as “true cinnamon,” this is the most expensive variety.
- Cassia: It is less expensive and is found in the majority of cinnamon-containing foods.
The differences between these two types are discussed below.
How Does Cinnamon Affect Diabetes?
Cinnamon has skyrocketed in popularity as many claim it’s a miracle ‘food’ for diabetics. But, how true is this? Here are some claimed benefits of cinnamon for diabetes.
Boosts Insulin Sensitivity
Diabetes occurs when the pancreas does not produce enough insulin, or the cells do not respond appropriately to insulin, leading to insulin resistance. Cinnamon may help people with diabetes by mimicking insulin’s effects, increasing glucose transport into cells, and thus, improving insulin sensitivity and blood sugar control .
In one study of seven men, cinnamon consumption increased insulin sensitivity immediately, leading, and this effect lasted at least 12 hours . Another study found that taking cinnamon for two weeks improved insulin sensitivity in eight men .
Decreases Fasting Blood Sugar Levels
Numerous studies have shown cinnamon’s efficacy in lowering fasting blood glucose.
A study of 543 people with type 2 diabetes showed reduced blood sugar by an average of 24 mg/dL (1.33 mmol/L) .
Studies on its effect on hemoglobin A1c, a measure of long-term blood sugar control, have produced mixed results. Some studies show significant drops in hemoglobin A1c while others show no change [5, 6, 7, 8]. The contradictory findings may be explained by differences in cinnamon dosage and prior blood sugar control.
Decreases Blood Sugar Levels Following Meals
Depending on the size and carbohydrate content of the meal, blood sugar levels can increase dramatically. That causes oxidative stress and inflammation, which lead to cell damage and can increase the risk of chronic disease [9, 10].
Some researchers believe that daily cinnamon use can help control post-meal blood sugar spikes by slowing digestion . Additionally, other research suggests that cinnamon inhibits digestive enzymes responsible for carbs breakdown in the small intestine, thus lowering blood sugar after meals [12, 13].
Other Health Benefits of Cinnamon
Cinnamon contains a high concentration of cinnamaldehyde, anti-inflammatory, and antioxidant compounds, which are believed to be responsible for most of cinnamon’s health benefits. The following are some health benefits of cinnamon in diabetes.
Antioxidants safeguard your body against the oxidative stress caused by free radicals, and cinnamon contains numerous antioxidants, including polyphenols [14, 15, 16].
Cinnamon emerged as the clear winner in a study comparing the antioxidant activity of 26 spices, even outperforming “superfoods” like garlic and oregano .
Cinnamon’s antioxidant effects are so potent that it can be used as a natural preservative for food! 
Inflammation is critical. It aids your body in fighting infections and repairing damaged tissue. However, chronic inflammation directed against your body’s tissues can become a problem. Cinnamon may be beneficial in this situation as its antioxidants have been shown in studies to have potent anti-inflammatory properties [19, 20].
May Lower Cardiovascular Disease Risk
Cinnamon may help prevent heart disease, the leading cause of death worldwide.
A daily dose of 1 gram (half a teaspoon) of cinnamon has been shown to improve blood markers in people with type 2 diabetes. In addition to lowering total cholesterol, triglycerides, and bad cholesterol, it also raises good cholesterol levels . When combined, these factors can significantly reduce your risk of heart disease by maintaining normal blood pressure and heart function.
An extensive review study recently concluded that just 120 mg of cinnamon daily might have these effects .
May Protect Against Neurodegenerative Diseases
Neurodegenerative diseases cause progressive brain cell loss. Alzheimer’s and Parkinson’s disease are two common types.
One of the hallmarks of Alzheimer’s disease is tau protein buildup in the brain, which cinnamon appears to inhibit [23, 24, 25].
In one study, cinnamon protected neurons, normalized neurotransmitter levels, and improved motor function in mice with Parkinson’s . However, human studies are warranted to confirm these benefits.
May Help Prevent Cancer
Uncontrolled cell growth is a hallmark of cancer, and cinnamon has been extensively researched for its anti-cancer properties. These anti-cancer effects have been studied mainly in lab and animal research. It slows tumor cell growth and blood vessel formation and appears to be toxic to cancer cells, killing them [27, 28, 29, 30, 31].
Nevertheless, cinnamon’s effect on living humans must be studied carefully.
Assists in Combating Bacterial and Fungal Infections
Cinnamaldehyde, one of cinnamon’s primary active ingredients, may help fight infections. Cinnamon oil can treat fungal respiratory infections and slow the growth of bacteria like Listeria and Salmonella [32, 33]. However, research shows that cinnamon does not reduce infections in other parts of the body.
Cinnamon’s antimicrobial properties may also help prevent tooth decay and bad breath as well [34, 35].
Aid in the Fight Against the HIV Virus
If left untreated, HIV weakens the immune system, eventually leading to AIDS.
Cinnamon from Cassia varieties may help fight HIV-1, the most common HIV strain in humans [36, 37].
In a study of 69 medicinal plants, cinnamon was the most effective treatment for HIV-infected cells . However, human clinical trials are still required to verify these findings.
Cassia vs. Ceylon: Which is Better?
Not all cinnamon is equal. Cassia is high in coumarin, which is toxic in large doses. While all cinnamon is beneficial to health, Cassia’s coumarin content may cause health problems in high doses .
Studies show that Ceylon cinnamon contains far less coumarin than Cassia cinnamon . Most cinnamon in supermarkets is the cheaper Cassia variety.
Side Effects of Cinnamon
Possibility of Liver Damage
Cassia cinnamon is high in coumarin, which harms the liver. Cassia cinnamon contains 7–18 milligrams (2.6 grams) of coumarin per teaspoon, whereas Ceylon cinnamon contains only trace amounts .
Tolerable daily dose of coumarin is 0.05 mg/pound (0.1 mg/kg) of body weight, or 5 mg for a 130 pound (59 kg) person. Hence, just a teaspoon of Cassia cinnamon may cause you to go over your daily limit .
Several studies have found that excessive coumarin consumption can cause liver toxicity [43, 44]. Hence, if you wish to take cinnamon supplements, follow the dose recommended by your healthcare professional.
Possibility of Increasing Cancer Risk
Excessive consumption of coumarin, found in Cassia cinnamon, has been linked to an increased risk of cancer in animals .
Excess coumarin consumption can also cause cancerous tumors in the lungs, liver, and kidneys in rats [46, 47, 48]. Some researchers believe coumarin damages DNA over time, increasing the risk of cancer .
The majority of coumarin research has been done on animals. Therefore, more human studies are needed to determine the exact link between cancer and coumarin.
Possibility of Mouth Sores
Some people get mouth sores after consuming cinnamon-flavored products [50, 51, 52]. Cinnamon contains cinnamaldehyde, a compound that can cause allergic reactions in large doses. Small amounts of the spice do not seem to cause this reaction, as saliva prevents prolonged chemical contact with the mouth.
Other cinnamaldehyde allergy symptoms include:
- White patches in the mouth
- A burning or itching sensation
- Tongue swelling
- Gum swelling
These symptoms, while not always severe, can be annoying . However, cinnamaldehyde will only cause mouth sores if you are allergic to it. A skin patch test can detect this type of allergy . Also, excessive cinnamon oil or cinnamon-flavored chewing gum consumption appears to cause mouth sores.
Could Result in Low Blood Sugar
Cinnamon is well known for lowering blood sugar.
Hence, a pinch of cinnamon may help lower blood sugar, but too much may cause it to drop too low, which leads to hypoglycemia in some people [55, 56, 57]. It can cause fatigue, dizziness, and even fainting .
Low blood sugar is most common in diabetics who consume blood-glucose-lowering medications. Cinnamon can enhance the effects of diabetes treatment medications, causing dangerously low blood sugar.
Excessive consumption of ground cinnamon may cause breathing difficulties. The spice’s delicate texture makes it easy to inhale. Inadvertently inhaling it can cause:
- Difficulty catching your breath
Cinnamaldehyde in cinnamon is a throat irritant. It may worsen existing breathing issues . Asthmatics and other people who have trouble breathing should avoid accidentally inhaling cinnamon.
Certain Medications May Interact
Cinnamon is generally safe in small to moderate amounts with most medications. But taking too much may cause issues if you have diabetes, heart disease, or liver disease.
Other than that, if you take liver-harming medications like paracetamol, acetaminophen, or statins, cinnamon may increase your risk of liver damage .
In addition, cinnamon may help lower blood sugar, which may amplify the effects of diabetes mellitus medications, causing dangerous blood sugar drops.
How to Take Cinnamon in Diabetes
While many studies have backed its blood-glucose-lowering effects, other studies do not arrive at similar conclusions. Furthermore, the American Diabetes Association does not advocate cinnamon’s use in diabetes treatment.
Plus, no agreement has been reached on the optimal amount to consume to reap the benefits while avoiding potential risk factors.
Typically, 1–6 grams of cinnamon per day were used in studies as a supplement or powder added to foods. According to one study, individuals who consumed 1, 3, or 6 grams of cinnamon daily decreased their blood sugar levels by the same amount .
Given that those taking the smallest dose experienced the same benefit as those taking the largest dose, so there may be no need to take large doses.
Furthermore, several studies have demonstrated that the coumarin content of Cassia cinnamon varies. As a result, it is prudent to consume no more than 0.5–1 gram of coumarin per day to avoid exceeding the tolerable daily intake of coumarin.
Ceylon cinnamon requires much less caution. Consuming up to 1.2 teaspoons (6 grams) daily should be considered safe in terms of coumarin content.
Bottomline: Can Cinnamon Reverse Diabetes?
Numerous studies have demonstrated that cinnamon can lower blood sugar and manage common diabetes complications, among other health benefits. Nevertheless, there is no unanimous agreement that cinnamon can treat or reverse diabetes.
If you intend to take cinnamon supplements or incorporate them into your meals to help lower your blood sugar, it is best to use Ceylon rather than Cassia.
While Ceylon cinnamon is more expensive, it contains more antioxidants and less coumarin, which can cause liver damage.
And always remember to consult your healthcare professional to find out if cinnamon is safe for you and which dose would suit you best!
Disclaimer: This article is only a guide. It does not substitute the advice given by your own healthcare professional. Before making any health-related decision, consult your healthcare professional.