Cinnamon's therapeutic uses
Cinnamon, commonly recognized as a spice, has a rich history of therapeutic uses, particularly in traditional medicine. It is derived from the bark of a Southeast Asian tree and is available in various forms, including oil, extract, and dried powder. While cinnamon is often associated with flavoring food, it has been explored for its potential health benefits, notably in managing diabetes and high cholesterol. Some studies suggest that cinnamon may improve blood sugar and cholesterol levels, although the evidence remains mixed and inconclusive.
Beyond metabolic health, cinnamon also exhibits anti-inflammatory, antimicrobial, and antioxidant properties, which may provide cardiovascular benefits and support cognitive function. Additionally, it has been used to aid digestive health by improving appetite and relieving symptoms of indigestion and diarrhea. However, while preliminary studies show promise, more rigorous human clinical trials are necessary to confirm these effects. Overall, while cinnamon is largely considered safe as a food spice, caution is advised regarding its concentrated forms, especially for certain populations such as pregnant women.
Cinnamon's therapeutic uses
- DEFINITION: Natural plant product used to treat specific health conditions.
- PRINCIPAL PROPOSED USES: Diabetes, high cholesterol
- OTHER PROPOSED USES: Anti-inflammatory, antimicrobial, antioxidant, cardiovascular benefits, cognitive function, digestive health, improving appetite, indigestion, polycystic ovary disease, ulcers
Overview
Most Americans consider cinnamon a simple flavoring, but in traditional Chinese medicine, it is one of the oldest remedies, prescribed for everything from diarrhea and chills to influenza and parasitic worms. Cinnamon comes from the bark of a small Southeast Asian evergreen tree and is available as an oil, extract, or dried powder. It is closely related to cassia (Cinnamon cassia) and contains many of the same components, but the bark and oils from Cinnamomum zeylanicum are thought to have a better flavor.
Therapeutic Dosages
Typical recommended dosages of ground cinnamon bark are 1 to 4 grams (g) daily. Cinnamon oil is generally used at a dose of 0.05 to 0.2 g daily.
Therapeutic Uses
Based on the results of one preliminary double-blind, placebo-controlled study, cinnamon has been widely advertised as an effective treatment for type 2 diabetes and high cholesterol. However, the evidence for this is mixed. Cinnamon may have additional cardiovascular benefits, such as lowering blood pressure, but more study is needed.
Germany’s Commission E approves cinnamon for improving appetite and relieving indigestion; however, these uses are not backed by reliable scientific evidence. Two animal studies weakly suggest that an oral extract of cinnamon bark may help prevent stomach ulcers. A 2023 study found that cinnamon improved diarrhea symptoms by altering the gut biome, and a 2022 study showed that cinnamon supplementation may improve appetite.
Cinnamon's anti-inflammatory and antioxidant properties may protect against free radicals that cause chronic health conditions. Early studies suggest cinnamon may also have cognitive benefits for brain health and memory.
Preliminary results from test-tube and animal studies suggest that cinnamon oil and cinnamon extract have antifungal, antibacterial, and antiparasitic properties. For example, cinnamon has been found to be active against Candida albicans, the fungus responsible for vaginal yeast infections and thrush (oral yeast infection), Helicobacter pylori (the bacterium that causes stomach ulcers), and even head lice. However, it is a long way from studies of this type to actual proof of effectiveness. Until cinnamon is tested in double-blind human trials, it remains unclear if it can successfully treat these or any other infections.
Scientific Evidence
Based on previous animal studies that had suggested the potential benefits of cinnamon for diabetes, researchers in Pakistan performed a double-blind, placebo-controlled trial. In this forty-day study, sixty people with type 2 diabetes were given cinnamon at a dose of 1, 3, or 6 g daily. The results reportedly indicated that the use of cinnamon improved blood sugar levels by 18 to 29 percent, total cholesterol by 12 to 26 percent, low-density lipoproteins (LDL, or bad cholesterol) by 7 to 27 percent, and triglycerides by 23 to 30 percent. These results were said to be statistically significant, compared with the beginning of the study and to the placebo group.
However, this study has some odd features. Most importantly, no significant difference in benefit was found between the various doses of cinnamon. This is called lack of a dose-related effect, and it generally casts doubt on the results of a study. The researchers counter that perhaps even 1 g of cinnamon is sufficient to produce the maximum cholesterol-lowering effect, and therefore, higher doses simply did not add any further benefit. Another problem with this study is that no improvements were seen in the placebo group. This too is unusual, and it also casts doubt on the results.
To replicate these results, a group of Dutch researchers performed a carefully designed six-week double-blind, placebo-controlled study of twenty-five people with diabetes. All participants were given 1.5 g of cinnamon daily. The results failed to show any detectable effect on blood sugar, insulin sensitivity, or cholesterol profile. Although this second study was smaller than the first because it had fewer groups, overall, its statistical validity is similar. These unsupportive results were confirmed in a Thai study enrolling sixty people: 1.5 g of cinnamon daily failed to produce any benefit. On the other hand, a double-blind study of seventy-nine people who used 3 g instead of 1.5 g daily did find that cinnamon improved blood sugar levels. A randomized trial involving fifty-eight people with type 2 diabetes also concluded that 2 g of cinnamon daily reduced HbA1c levels (a measurement of blood sugar levels over time) and high blood pressure.
In another small study involving twenty-two prediabetic patients with metabolic syndrome, researchers found that an extract containing 500 mg cinnamon once daily effectively modestly reduced fasting blood sugar and systolic blood pressure and increased lean body weight. However, the low dosage of cinnamon used raises concerns about the reliability of the results. A very small study that evaluated cinnamon for improving blood sugar control in women with polycystic ovary disease found evidence of benefit.
Although double-blind, placebo-controlled trials of cinnamon for diabetes and cardiovascular benefits continued, it would be premature to consider cinnamon an evidence-based treatment for type 2 diabetes or heart health, but it has shown some promise. However, a meta-analysis (formal statistical review) of all published evidence concluded that, thus far, cinnamon has not been shown to have any effect on blood sugar levels in people with diabetes. The evidence regarding cinnamon as a treatment for diabetes is highly inconsistent, suggesting that if cinnamon is effective, its benefits are minimal at most.
Double-blind, placebo-controlled trials were conducted on cinnamon for additional therapeutic uses. These studies showed benefits for digestive health, specifically in easing diarrhea symptoms and stimulating appetite. Preliminary trials also suggested cinnamon could improve cognitive function and memory.
Safety Issues
As a widely used food spice, ground cinnamon bark is believed to be safe. However, cinnamon’s essential oil is much more concentrated than the powdered bark commonly used for baking. There is some evidence that high doses of cinnamon oil might depress the central nervous system. Germany’s Commission E recommends that pregnant women avoid taking cinnamon oil or high doses of the bark. Maximum safe doses in young children, nursing women, or individuals with severe liver or kidney disease have not been determined.
Cinnamon bark oil may cause flushing and a burning sensation when used topically. Some people have reported strong burning sensations or mouth ulcers after chewing cinnamon-flavored gum or candy. However, these reactions disappeared within days of discontinuing the gum.
Bibliography
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