High-dose cinnamon may help control prediabetes blood glucose levels
Taking a cinnamon supplement may help to manage blood glucose levels and slow progression from prediabetes to type 2 diabetes, according to a study published in the Journal of the Endocrine Society.
“Although cinnamon is primarily known and used as a spice, at the higher doses employed in our study, cinnamon may also counteract certain defects of glucose metabolism that occur prior to developing type 2 diabetes,” Giulio R. Romeo, MD, an adult endocrinologist and assistant investigator at Joslin Diabetes Center and instructor at Harvard Medical School, told Healio.
Romeo and colleagues recruited 51 adults from the Kyung Hee University Medical Center in Seoul, South Korea, and from the Joslin Diabetes Center in Boston from 2017 to 2018. All participants had prediabetes, defined as a fasting plasma glucose level between 100 mg/dL and 125 mg/dL; impaired glucose tolerance between 140 mg/dL and 199 mg/dL, based on a 75 g oral glucose tolerance test; or an HbA1c of between 5.7% and 6.4%.
Participants were randomly assigned to a cinnamon capsule (n = 27) or a placebo capsule (n = 24) three times a day for 12 weeks. The cinnamon capsules consisted of 300 mg of cinnamon extract and 200 mg of Cinnamomum burmannii powder. The placebo contained cellulose, caramel food coloring and cinnamon incense. At 6- and 12-week follow-up visits, researchers determined adherence through counting capsules returned by the participants and self-reporting, and recorded data on anthropometric measures, HbA1c, FPG, OGTT, fasting insulin and fasting lipids.
FPG levels were similar between the cinnamon and placebo groups at baseline and 6 weeks, but at 12 weeks, the placebo group had a mean increase in FPG of 4.5 mg/dL compared with no statistically significant change in the cinnamon group, for a mean difference of about 5 mg/dL between the groups (114 mg/dL for placebo vs. 108 mg/dL for cinnamon; P < .01). Additionally, during the OGTT, the cinnamon group had a significant decrease in area under the curve for plasma glucose from baseline (21,389 mg/dL/120 min) to 12 weeks (19,946 mg/dL/120 min; P < .05). No change was observed in the placebo group. The cinnamon group had a decrease in plasma glucose at 2 hours following the OGTT from baseline to 12 weeks (–20 mg/dL; P < .01) vs. no change for the placebo group.
The cinnamon group experienced a 0.13% decrease in HbA1c from baseline to 12 weeks, for a 0.2% difference between the cinnamon and placebo groups at the end of the study (P < .01). For participants who had an HbA1c between 5.7% and 6.4% at baseline, seven of 14 in the cinnamon group saw levels drop below 5.7% at 12 weeks, whereas only one of 10 in the placebo group saw a similar drop (P < .05).
These data suggest that a cinnamon supplement could recategorize some adults with prediabetes to normal glycemic status, according to the researchers.
“If our findings were to be confirmed in longer and larger studies, cinnamon could be an adjunct therapy — in addition to lifestyle interventions — for preventing the onset of type 2 diabetes in an at-risk population,” Romeo said.
The rate of adverse events was 29.2% for both groups. All adverse events were deemed unlikely to be related to the study, and no serious events were reported.
Romeo said longer studies are needed to specifically look at whether long-term treatment with cinnamon can slow the progression from prediabetes to type 2 diabetes.
For more information:
Giulio R. Romeo, MD, can be reached at Joslin Diabetes Center, One Joslin Place, Boston, MA 02215; email: email@example.com.