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Open Source Apothecary At Home / The herbs
A spice with blood-sugar evidence — and a coumarin problem that decides which cinnamon you buy. — Cinnamomum verum, C. cassia
remedyCinnamon (Cinnamomum) has randomised trial evidence for small reductions in fasting glucose and cholesterol in type 2 diabetes. The effect is modest, inconsistent between trials, and considerably smaller than the effect of diet, weight and exercise.
The species distinction is a safety issue, not a connoisseur's one. Cassia cinnamon (the common supermarket product) contains coumarin, which is hepatotoxic at sustained high intake. Ceylon cinnamon (C. verum) has very little coumarin. For occasional culinary use cassia is fine; for daily medicinal doses, use Ceylon. This is one of the clearest cases in the handbook where the botanical species determines safety.
Growing cinnamon here is not realistic — it is a tropical tree requiring a wet tropical climate. It can be kept as a novelty houseplant but will not produce usable bark in this climate; buy it instead.
Diabetes is not managed with cinnamon. The evidence supports it as a small adjunct at most, and it is not a substitute for metformin, diet or exercise.
The data suggest that cinnamon improves the glycemic and lipid profile and reduces the BMI, particularly in DM2 patients who receive cinnamon supplementation in capsule form and at a dose of ≤2 g/day.PubMed 38917435 ↗
Although many randomized controlled trials (RCTs) have revealed the benefits of cinnamon on type 2 diabetes mellitus (T2DM), the effects of cinnamon supplementation on glycemic control in patients with T2DM are inconclusive.PubMed 37818728 ↗
The consumption of cinnamon is associated with a statistically significant decrease in levels of fasting plasma glucose, total cholesterol, LDL-C, and triglyceride levels, and an increase in HDL-C levels; however, no significant effect on hemoglobin A1c was found.PubMed 24019277 ↗
There is insufficient evidence to support the use of cinnamon for type 1 or type 2 diabetes mellitus.PubMed 22972104 ↗
This randomized controlled trial developed and tested a CZ-based intervention for Type 2 Diabetes, demonstrating its promising efficacy and safety.PubMed 41412108 ↗
| | | |---|---| | Life | Tropical evergreen tree | | Reality here | Not growable for bark in zone 6a — buy it | | Container | Possible as a houseplant; will not yield usable bark | | Note | If you buy it, buy Ceylon for daily use |
There is no useful home cultivation for cinnamon in this climate. This entry exists to make the species distinction and to say plainly that this is a buy-it herb.
Culinary — cassia is fine occasionally.
Daily medicinal use — Ceylon cinnamon, 1-2 g daily. The trials used around 1-6 g.
Tea — a stick simmered 10 minutes.
With food — cinnamon with carbohydrate slows gastric emptying slightly.
Check the label for the species — "cinnamon" on a label usually means cassia.