Cinnamon is one of the most-studied spices for blood sugar. The evidence is real but modest — and the type matters.
What the studies show
- Meta-analyses: cinnamon lowers fasting glucose by 5–25 mg/dL
- HbA1c reduction: 0.27% on average
- Effect is more pronounced in people with poor baseline control
- Effect plateaus after 8–12 weeks for some
Ceylon vs Cassia cinnamon
There are two main types:
### Cassia (the usual supermarket type) - Cheaper - Stronger flavor - Contains coumarin, which can damage the liver in high doses - Limit: 1 tsp/day max
### Ceylon ("true cinnamon") - More expensive - Milder, sweeter flavor - Minimal coumarin - Safe at higher doses
For long-term daily use, choose Ceylon.
Effective dose
- 1–3g per day (½ to 1 teaspoon)
- Split into 2 doses for better effect
- Take with meals containing carbs
How to use it
- Sprinkle on Greek yogurt, oats, coffee
- Stir into smoothies
- Use in spice rubs and curries
- Capsules if you don't like the taste
Realistic expectations
Cinnamon is not a substitute for diet, exercise or medication. The effect is real but small — think of it as a 5% bonus on top of the fundamentals.
Cautions
- Cassia in high doses can affect the liver — don't take cinnamon supplements daily without coumarin-free assurance
- Cinnamon can mildly thin blood — caution with blood thinners
- May interact with insulin/sulfonylureas — monitor for lows
- Discuss with your doctor before starting