Guide
Who should not take cinnamon?
A few groups should ask a doctor before using any cinnamon supplement: liver conditions, certain medications, known cinnamon sensitivity, and pregnancy, nursing or childhood.
Cinnamon supplements warrant extra caution for a few groups: anyone with a liver condition or taking a medication that's hard on the liver, anyone on medication that already lowers blood sugar, anyone with a known sensitivity to cinnamon, and anyone pregnant, nursing, or considering it for a child should check with a doctor first.
Liver conditions or liver-processed medication
Cassia cinnamon's coumarin content has been linked to liver injury at high, sustained intakes, including in at least one case report involving a statin medication (see cinnamon side effects for the specifics). If you have a liver condition, or take a medication your doctor has told you is processed by or hard on the liver, ask your doctor before adding a cinnamon supplement, particularly a cassia-based one.
Medication that lowers blood sugar
Some cinnamon research has found an effect on blood sugar in people who already have it elevated. If you take a medication for that reason — including insulin or a prescription that lowers blood sugar — ask your doctor before adding cinnamon, since combining two glucose-lowering effects can push levels lower than either alone. Cinnamon and medications: what to check covers this in more detail.
Known sensitivity to cinnamon
Cinnamon-flavored products are a documented cause of allergic contact reactions in the mouth (cinnamon contact stomatitis). Anyone who has reacted to cinnamon gum, candy, toothpaste or food before should be cautious about a concentrated capsule form too, and stop if any mouth or skin irritation appears.
Pregnancy, nursing, and children
We haven't found dedicated safety research on concentrated cinnamon supplements in pregnancy or while nursing at any specific dose, which is itself a reason for caution rather than reassurance — ask a doctor before using one in either situation. Cinnamon supplements aren't formulated or dosed for children; a pediatrician, not a general adult dose, is the right source for anything given to a child.
Questions people ask
Who should not take cinnamon supplements?
People with liver conditions, anyone on medication that's processed by the liver or that already lowers blood sugar, anyone with a known sensitivity to cinnamon, and anyone pregnant, nursing, or thinking about giving it to a child should ask a doctor first.
Is cinnamon supplement bad for kidneys?
We haven't found dedicated research on cinnamon and kidney function specifically. If you have a kidney condition, ask a doctor before starting any new supplement, cinnamon included.
Can diabetics take cinnamon supplements?
Anyone taking medication for diabetes should ask a doctor before adding cinnamon, because of the possibility of an additive glucose-lowering effect. Cinnamon is not a treatment for diabetes and shouldn't replace prescribed medication.
Related reading: cinnamon side effects and cinnamon and medications: what to check.
Sources
- Assessment of coumarin levels in ground cinnamon available in the Czech retail market Retail cassia cinnamon samples averaged 2,650-7,017 mg of coumarin per kilogram; a Ceylon cinnamon sample tested had none.
- Do cinnamon supplements cause acute hepatitis? A case report described a woman who developed hepatitis after combining a cinnamon supplement with a statin medication; symptoms resolved when both were stopped, and the statin alone was later tolerated.
- Oral adverse reactions due to cinnamon-flavoured chewing gums consumption A review of case reports found cinnamon-flavoured chewing gum and similar products are a documented cause of oral contact reactions (cinnamon contact stomatitis), which resolve when the product is stopped.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.