Cinnamon Supplements May Be Putting Your Health at Risk Without You Even Knowing It
Nikhil Prasad Fact checked by:Thailand Medical News Team May 15, 2025 7 hours, 34 minutes ago
Medical News: Cinnamon may be a beloved kitchen staple and a common ingredient in many traditional health remedies, but scientists are now raising serious concerns about its potential to disrupt the effectiveness of prescription medications. A new study conducted by researchers from the University of Mississippi in the United States and the University of Milan in Italy warns that highly concentrated cinnamon supplements, particularly those containing cinnamaldehyde, could interfere with how the body processes certain drugs.
Cinnamon Supplements May Be Putting Your Health at Risk Without You Even Knowing It
According to the findings, cinnamaldehyde—the compound that gives cinnamon its distinctive smell and flavor—may significantly influence key receptors responsible for drug metabolism. This
Medical News report highlights how even natural remedies, when misused or consumed excessively, may become a hidden danger for people managing chronic illnesses or those on long-term medications.
Cinnamon’s Medicinal Appeal May Mask a Hidden Risk
For centuries, cinnamon has been treasured in traditional healing systems for its supposed benefits in managing blood sugar, supporting heart health, and reducing inflammation. Today, it is a staple in both kitchens and pharmacies, especially in the form of capsules, oils, and extracts labeled as dietary supplements. However, the new study, published in Food Chemistry: Molecular Sciences, presents strong evidence that these supplements may not be as benign as once believed.
The team, led by principal scientist Shabana Khan at the University of Mississippi’s National Center for Natural Products Research, discovered that cinnamaldehyde significantly activates xenobiotic receptors in the body—specifically PXR (pregnane X receptor) and AhR (aryl hydrocarbon receptor). These receptors regulate how the body metabolizes and clears various drugs. When these receptors are overstimulated, medications can be broken down too quickly, reducing their effectiveness.
“Health concerns could arise if excessive amounts of supplements are consumed without the knowledge of the health care provider or prescriber of the medications,” warned Khan. “This could lead to rapid clearance of the prescription medicine from the body, and that could result in making the medicine less effective.”
How Cinnamon Is Processed in the Body
The researchers conducted extensive laboratory experiments simulating conditions of both the fasted and fed human digestive systems. They found that cinnamaldehyde has a bioaccessibility rate of 100%, meaning it is fully available for absorption in both gastric and intestinal environments. The compound is highly stable, indicating that it can withstand digestive processes without breaking down prematurely.
Further testing revealed that once absorbed, cinnamaldehyde is rapidly converted by liver enzymes into cinnamic acid. This metabolic conversion was found to occur in under 10 minutes durin
g testing with human liver microsomes (HLMs) and liver S-9 fractions. While this transformation is part of the body’s natural detoxification process, the study showed that both cinnamaldehyde and its metabolites can influence drug-metabolizing enzymes like CYP2C9 and CYP1A2, potentially creating herb-drug interactions (HDIs).
Cassia Cinnamon and Coumarin Content Raise Additional Red Flags
Not all cinnamon is created equal. The most commonly available variety in grocery stores is Cassia cinnamon, which is cheaper but contains significantly higher levels of coumarin, a natural blood thinner. This adds an extra layer of concern for individuals taking anticoagulant medications like warfarin.
In contrast, Ceylon or “true” cinnamon, sourced mainly from Sri Lanka, has a much lower coumarin content and is considered safer in this regard. Dr. Amar Chittiboyina, associate director of the research center, stressed the need to understand these differences when using cinnamon therapeutically.
“Coumarin’s anticoagulant properties can be hazardous for individuals on blood thinners,” Chittiboyina noted.
Cinnamon Oil and Its Unique Effects
Interestingly, cinnamon oil, often used in topical applications and as a food flavoring, did not appear to carry the same risks as ground bark when it came to herb-drug interactions. However, at higher doses, cinnamon oil itself activated AhR significantly—by more than 12-fold in some experimental conditions.
The research also found that while cinnamaldehyde alone did not trigger AhR activation, cinnamon oil did—most likely due to the presence of other bioactive compounds such as flavonoids. These findings suggest that cinnamon oil’s full pharmacological profile needs closer investigation.
The Bigger Picture for People with Chronic Conditions
Lead researcher Bill Gurley emphasized that individuals suffering from chronic diseases like diabetes, hypertension, cancer, asthma, HIV, and depression need to be particularly cautious about using cinnamon supplements. These individuals are often on multiple prescription medications, making them more vulnerable to potential herb-drug interactions.
“We know there’s a potential for cinnamaldehyde to activate these receptors that can pose a risk for drug interactions,” said Gurley. “That’s what could happen, but we won’t know exactly what will happen until we do a clinical study.”
Until then, the researchers strongly urge the public to consult with healthcare providers before adding cinnamon supplements to their health regimen.
Detailed Laboratory Findings
Key results from the study include:
-
Complete Bioaccessibility: Cinnamaldehyde remained 100% bioaccessible in both fed and fasted simulated gastric and intestinal environments.
-
Rapid Metabolism: Over 90% of cinnamaldehyde was metabolized within 10 minutes when exposed to liver enzymes, converting quickly into cinnamic acid.
-
Activation of Xenobiotic Receptors: Cinnamon oil and cinnamic acid significantly activated PXR in intestinal cells (LS174T), while cinnamon oil alone activated AhR up to 13-fold.
-
Enzyme Inhibition: Cinnamon oil and cinnamaldehyde inhibited two major drug-metabolizing enzymes—CYP2C9 and CYP1A2—while showing no significant effect on CYP3A4 or CYP2D6.
-
Modest Cell Toxicity at High Doses: While lower concentrations of cinnamon compounds had no effect on human cells, very high concentrations (100 μg/mL) began to show marginal toxicity.
A Call for Clinical Studies and Greater Awareness
Although the current findings are based on in vitro (lab-based) studies, the implications are serious enough to warrant caution. The researchers call for clinical trials to further evaluate how these interactions play out in real-life human conditions. Until then, the best approach is moderation and professional guidance.
In conclusion, while cinnamon offers a range of health benefits when consumed in moderate amounts, its use as a high-dose supplement could pose hidden dangers. The ability of cinnamaldehyde and cinnamon oil to activate critical drug-processing receptors and interfere with enzymes responsible for metabolizing prescription drugs is a red flag for consumers, particularly those with chronic illnesses or complex treatment regimens. Over time, such interactions may lead to a decrease in medication efficacy or unexpected side effects. Thus, anyone considering cinnamon supplements should first consult a healthcare provider and never assume that natural means risk-free.
The study findings were published in the peer-reviewed journal: Food Chemistry Molecular Sciences
https://www.sciencedirect.com/science/article/pii/S2666566224000443
For the latest on Herbs and Phytochemicals, keep on logging to Thailand
Medical News.
Read Also:
https://www.thailandmedical.news/news/turkish-study-discovers-cinnamic-acid-compounds-as-a-new-antibacterial-hope-against-drug-resistant-infections
https://www.thailandmedical.news/news/japanese-study-finds-that-the-flavors-and-fragrance-extracts-of-cinnamon-and-mint-can-protect-against-covid-19
https://www.thailandmedical.news/news/cinnamon-extract-offers-hope-for-joint-pain-relief
https://www.thailandmedical.news/news/study-finds-that-esters-of-sinapic-acid-a-cinnamic-derivative-exhibits-antiviral-potential-against-oc43-and-sars-cov-2-viruses
https://www.thailandmedical.news/news/medical-news-italian-study-shows-that-cinnamaldehyde-from-cinnamon-is-an-effective-adjuvant-for-covid-19-prevention-and-treatment
https://www.thailandmedical.news/news/italian-study-finds-cinnamaldehyde-is-an-effective-adjuvant-therapeutic-compound-for-reducing-inflammation-in-covid-19
https://www.thailandmedical.news/news/breaking-news-plant-based-compound-dicoumarol-emerges-as-promising-post-exposure-prophylactic-for-omicron-variant-of-sars-cov-2
https://www.thailandmedical.news/news/cinnamon-the-natural-remedy-for-flu-infections-and-beyond
https://www.thailandmedical.news/news/covid-19-herbs-german-american-study-shows-that-cinnamaldehyde-from-cinnamon-is-a-good-supplement-with-dexamethasone-for-treating-covid-19
https://www.thailandmedical.news/news/study-shows-curcumin,-cinnamon-and-resveratrol-health-supplements-effective-in-prevention-and-management-of-diabetes
https://www.thailandmedical.news/pages/thailand_doctors_listings
Share
Tweet
Share
