Cinnamon
TL;DR
Common spice with insulin-sensitizing properties
Moderate evidence for reducing fasting blood sugar in Type 2 diabetics
Contains cinnamaldehyde, which mimics insulin and improves glucose uptake
Ceylon cinnamon is safer for long-term use than Cassia
Generally safe; very cheap
Cost: ~$5-10/month
Best for: Mild blood sugar support, metabolic health adjunct
What it is
Cinnamon is a spice derived from the inner bark of trees from the Cinnamomum genus. While it's a kitchen staple, its medicinal use for 'sugar sickness' dates back centuries. The active compounds, specifically cinnamaldehyde and water-soluble polymers, help cells respond more efficiently to insulin.
There are two main types: Cassia (the common grocery store variety) and Ceylon ('True' cinnamon). Cassia contains high levels of coumarin, which can be toxic to the liver in large doses. For therapeutic supplementation, Ceylon or a water-soluble extract is preferred.
What the research says
Cinnamon is a useful 'add-on' but not a cure-all. Fasting Glucose. A 2013 meta-analysis of 10 RCTs found that cinnamon significantly reduced fasting blood glucose and LDL cholesterol. HbA1c. The data on HbA1c (long-term sugar control) is more mixed; some studies show a benefit, while others show no change. Mechanism. It works by slowing the emptying of the stomach and inhibiting digestive enzymes, leading to a slower rise in blood sugar after meals. Recommendation. Best for those with pre-diabetes or as a secondary support for Type 2 diabetes.
Cinnamon on Amazon
*Link is just for your convenience - we do not make any fees
Safety
Generally safe. However, Cassia cinnamon contains coumarin, which can cause liver damage if consumed in large amounts daily. Always opt for Ceylon cinnamon or 'Coumarin-free' extracts for long-term use.
Interactions
- Diabetes Meds: May have an additive effect with Insulin or Sulfonylureas.
- Blood Thinners: Cassia (but not Ceylon) may interact with Warfarin due to coumarins.
Dosing
Standard Dose: 1-2 grams of Ceylon powder daily, or 250-500 mg of a concentrated water-soluble extract (like Cinnulin PF). Timing: Take with or just before carb-heavy meals.
Cost
Extremely cheap. $5-10 per month.
The bottom line
Cinnamon is a low-risk, low-cost way to nudge your blood sugar in the right direction. It's not as powerful as berberine, but it's much easier on the stomach and the wallet.
Sources for this page include published meta-analyses, systematic reviews, and NIH dietary supplement fact sheets. All claims reflect the evidence as of early 2026.
This is not medical advice. Consult your healthcare provider before starting any supplement, especially if you take medications.