This article has been substantially updated for readability and quality of evidence based on new publications.
People want the easy way to correct their health issues. They want to imbue a magical quality to “natural” products to make themselves healthier. They don’t want to take one of those evil Big Pharma drugs. Or put in the discipline or effort to reverse a chronic disease. If all that was not true, we probably wouldn’t see a million advertisements for supplements and “natural” foods that make you thinner, healthier, smarter, stronger, better. Of course, if even 1% of the claims (or outright fabrications) made by these hawkers of these supplements were supported by real science, physicians and Big Pharma would be unnecessary.
One of the diseases for which everyone is searching for a panacea is diabetes. It is essentially a disease of blood glucose management and is really several, unrelated diseases. Type 1 diabetes mellitus, once known as juvenile diabetes or insulin-dependent diabetes, results from a lack of insulin production by the pancreas. Until insulin was discovered and isolated, type 1 diabetes was essentially a death sentence. And today, with bioengineered human insulin (until the 1980’s, when recombinant DNA insulin was manufactured, insulin was purified from pigs), patients can live relatively normal, healthy lives with type 1 diabetes. Most individuals contract the disease in childhood, although one form, latent autoimmune diabetes of adults (LADA) is very similar to Type 1 diabetes, but the autoimmune disease strikes well after the common ages of Type 1. It is still treated with insulin.
In case there’s some confusion, as of today, type 1 diabetes cannot be cured. It can only be treated with insulin.
There is a form of diabetes called gestational diabetes, which results in high blood sugars in pregnant women, usually in the third trimester. Unfortunately, it is not well understood what causes it, and if it remains untreated, it could lead to other types of diabetes.
Type 2 diabetes is the most prevalent form, making up about 90-95% of all diabetes, and is a type of metabolic disease that can be treated without medication through weight loss, dietary modification and exercise. However, since all of those treatments are hard work, oral diabetes medications and insulin are eventually prescribed for treatment of the disease, when the blood glucose remains out of control. There is a strong correlation between type 2 diabetes and obesity, although there are other risk factors like genetics and sleep habits. Across the world, type 2 diabetes has skyrocket from 30 million in 1985 to 285 million in 2010. In the USA, 8.3% of the population has diabetes, which costs the country about $116 billion in direct medical spending.
Recently, a paper was published, in fact, a systematic review which I consider to be near the highest top level of scientific publication, that claimed that consuming cinnamon might reduce blood glucose levels. Maybe there is an easy way. Sprinkle cinnamon on everything, and there you go. So let’s take a look at this magical spice, and what it might do for diabetes.
The meta-analysis included 543 patients in 10 different randomized clinical trials (or an average of 54 per clinical trial, an extremely small number). In fact, the range of patient numbers in each arm of these studies ranged from a low of 7 (really, 7 patients?) to a high of 30. I would contend that rolling up averages from a bunch of small studies doesn’t necessarily increase the statistical power of the studies. In fact, it might exacerbate the statistical issues.
One of the more frustrating aspects of this analysis is that they claim that cinnamon reduces blood glucose by 24.59 mg/dL of blood. Well, you might think that is a great reduction, except it is significantly less than a reduction of 58 mg/dL shown by one of the more common oral diabetic medications, metformin. Furthermore, the authors frustratingly did not include the actual blood glucose level but just the reduction. A drop from 240 to 216, or a reduction of 24 mg/dL, is not necessarily clinically significant. In fact, at that level, the patient still has significant risks from complications of diabetes over both the long and short term. Finally, the systematic review showed no reduction in hemoglobin A1C levels, an important blood marker, which provides information about the long-term changes in a patient’s blood glucose. In other words, cinnamon induced clinically insignificant decreases in blood glucose, but, more importantly, didn’t reduce the one diagnostic marker that would indicate a reduction of blood glucose over a longer period of time.
Another systematic review, published in 2012, showed nearly the same results for cinnamon–reduction in blood glucose only 1-10% of what has been observed with other types of oral diabetes medication. And, as we’ve seen before, the reduction in blood glucose is so small as to be clinically insignificant.
Another meta-review (highlighting the importance of not Cherry Picking peer-reviewed papers), published the respected journal Diabetes Care, also examined cinnamon’s effect on diabetes. Their unsurprising conclusion: “Cinnamon does not appear to improve A1C, FBG, or lipid parameters in patients with type 1 or type 2 diabetes.”
Now, some might then conclude if a few grams of cinnamon might reduce blood sugar, then maybe a whole bunch of it will treat diabetes. Even though the Naturalistic Fallacy might make one think that good, natural cinnamon is safer than Big Pharma’s drugs, it would be an incorrect assumption. Some kinds of cinnamon contain coumarin, a compound that could be toxic at higher levels. Even if the risk is moderate, the evidence of efficacy (at least with diabetes) is lacking. But it is not logical to take even a slight risk for a minor or probably nonexistent effect.
Current treatments for all forms of diabetes are inexpensive, well tolerated and do what they’re supposed to do. And if you’re looking for a “natural” way to control blood sugars, there is nothing more natural than human insulin to do its job in controlling blood sugar–admittedly, insulin is only appropriate for type 1 and certain kinds of type 2.
In conclusion, the evidence for the clinical usefulness of cinnamon in treating blood glucose levels is remarkably weak, if not nonexistent. If you have been diagnosed with any form of type 1 diabetes, there is simply one treatment–insulin injections. If you’ve been diagnosed with pre-diabetes (the preliminary step before type 2 diabetes) or full-blown type 2 diabetes, well, there’s losing weight and exercise, followed by certain oral diabetic medications. Yeah, I know it’s hard. There’s not going to be something as easy as downing a cinnamon pill.
- Akilen R, Tsiami A, Devendra D, Robinson N. Cinnamon in glycaemic control: Systematic review and meta analysis. Clin Nutr. 2012 Oct;31(5):609-15. doi: 10.1016/j.clnu.2012.04.003. Epub 2012 May 12. Review. PubMed PMID: 22579946.
- Allen RW, Schwartzman E, Baker WL, Coleman CI, Phung OJ. Cinnamon use in type 2 diabetes: an updated systematic review and meta-analysis. Ann Fam Med. 2013 Sep-Oct;11(5):452-9. doi: 10.1370/afm.1517. PubMed PMID: 24019277; PubMed Central PMCID: PMC3767714.
- Baker WL, Gutierrez-Williams G, White CM, Kluger J, Coleman CI. Effect of cinnamon on glucose control and lipid parameters. Diabetes Care. 2008 Jan;31(1):41-3. Epub 2007 Oct 1. PubMed PMID: 17909085.
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- Risérus U, Willett WC, Hu FB. Dietary fats and prevention of type 2 diabetes. Prog Lipid Res. 2009 Jan;48(1):44-51. doi: 10.1016/j.plipres.2008.10.002. Epub 2008 Nov 7. Review. PubMed PMID: 19032965; PubMed Central PMCID: PMC2654180.
- Smyth S, Heron A. Diabetes and obesity: the twin epidemics. Nat Med. 2006 Jan;12(1):75-80. PubMed PMID: 16397575.