Ceylon Cinnamon Benefits: 8 Claims Scored on Human Studies, Plus the Coumarin Numbers

or read the scores first ↓

Sold direct by Dosera · 30-day money-back guarantee, nothing to send back · free US shipping

3 things most people get wrong about Ceylon cinnamon

1One teaspoon of the cinnamon in most US kitchens can pass the daily liver limit. Read why ↓
2In one market check, most samples sold as "cinnamon" were not true Ceylon at all. Read why ↓
3Owners say the studies only used cassia. The newest one, with 210 adults, did not. Read why ↓

Will cinnamon bring my morning number down, and is it safe?

"My numbers were still high in the morning - 115-130," one WebMD reviewer wrote. That is where most people start. Then the worry: "I have read so many posts about 'cinnamon' causing liver damage." And the doubt: "Unless you specifically look for ceylon you probably have cassia."

So there are three questions. Will it move my morning number? Is it safe every day? Is the bottle really Ceylon? The scores below answer the first one, claim by claim.

A woman in her sixties at her kitchen table comparing a grocery-store cinnamon jar with a capsule bottle — The jar in most kitchens is cassia, and the label rarely says so.

What to look for on a Ceylon label

Cinnamomum verum or Cinnamomum zeylanicum printed on the label
A coumarin number on the label or the maker's page
The mg per capsule and the capsules per serving, both clear
Bark powder you can see and smell when you open a capsule
Every batch lab-tested
The full price shown before you pay, and a money-back guarantee you can use

What to leave on the shelf

"Cinnamon" with no species named (in the US that usually means cassia)
"Cinnamon complex" blends that hide the amount of each herb
Softgels full of oil with a vague amount of cinnamon
"7,200 mg equivalent" math in place of real milligrams
Gummies with a few hundred milligrams and added sugar
Ad offers that sign you up for monthly shipments you did not ask for

The Dosera bottle we picked ticks every box on the left. See it ($17.50 a bottle) »

Does Ceylon cinnamon work? All 8 claims, scored

Each claim is scored out of 100 on three things: how many human studies back it, how big the effect was, and whether the studies agree. The weights are printed further down. A low score means small or mixed studies. It is not a safety grade.

Rank	Claim	Score	Dose in studies	Time to notice	People studied
1	Lowers fasting blood sugarThe best-supported claim, and the one most people buy cinnamon for. The morning number fell in most studies, though by different amounts.	C+62	120 mg to 6 g a day	2 to 4 weeks on a meter	543 in 10 studies; 210 in a Ceylon-only study
2	Lowers triglycerides and total cholesterolTriglycerides and total cholesterol came down in pooled studies. LDL, the one doctors watch most, did not move for sure.	C55	Mostly 1 to 3 g a day	8 to 12 weeks, then a blood test	750 in 13 studies
3	Smaller after-meal spikesA clear effect in a small study at 6 grams with the meal. At capsule doses, the evidence is thinner.	C50	6 g with the meal	The same meal	14 in the key study
4	Lowers A1cMixed. Two studies found a drop, but the pooled reviews did not. Do not expect your A1c to move much on cinnamon alone.	D47	1 g a day; 250 to 500 mg Ceylon extract	3 to 4 months	543 pooled; 109; 210
5	Lowers blood pressureA few points at most, and the reviews do not agree on the top number.	D45	2 g a day or less	8 weeks or more	641 in 9 studies
6	Antioxidant and inflammation markersLab markers moved in small studies. Nobody has shown that you would feel a difference.	D42	1.5 to 4 g a day	8 to 12 weeks	12 small studies
7	PCOS: cycles and insulinTwo small studies with promising results. Too few women to be sure.	D37	1.5 g a day	12 weeks to 6 months	45 and 66 women
8	Body weightAbout 2 pounds over several months in pooled studies. Not a reason to buy it.	D36	2 g a day or more	12 weeks or more	786 in 12 studies

1Lowers fasting blood sugarC+62
The best-supported claim, and the one most people buy cinnamon for. The morning number fell in most studies, though by different amounts.
Dose in studies
120 mg to 6 g a day
Time to notice
2 to 4 weeks on a meter
People studied
543 in 10 studies; 210 in a Ceylon-only study
2Lowers triglycerides and total cholesterolC55
Triglycerides and total cholesterol came down in pooled studies. LDL, the one doctors watch most, did not move for sure.
Dose in studies
Mostly 1 to 3 g a day
Time to notice
8 to 12 weeks, then a blood test
People studied
750 in 13 studies
3Smaller after-meal spikesC50
A clear effect in a small study at 6 grams with the meal. At capsule doses, the evidence is thinner.
Dose in studies
6 g with the meal
Time to notice
The same meal
People studied
14 in the key study
4Lowers A1cD47
Mixed. Two studies found a drop, but the pooled reviews did not. Do not expect your A1c to move much on cinnamon alone.
Dose in studies
1 g a day; 250 to 500 mg Ceylon extract
Time to notice
3 to 4 months
People studied
543 pooled; 109; 210
5Lowers blood pressureD45
A few points at most, and the reviews do not agree on the top number.
Dose in studies
2 g a day or less
Time to notice
8 weeks or more
People studied
641 in 9 studies
6Antioxidant and inflammation markersD42
Lab markers moved in small studies. Nobody has shown that you would feel a difference.
Dose in studies
1.5 to 4 g a day
Time to notice
8 to 12 weeks
People studied
12 small studies
7PCOS: cycles and insulinD37
Two small studies with promising results. Too few women to be sure.
Dose in studies
1.5 g a day
Time to notice
12 weeks to 6 months
People studied
45 and 66 women
8Body weightD36
About 2 pounds over several months in pooled studies. Not a reason to buy it.
Dose in studies
2 g a day or more
Time to notice
12 weeks or more
People studied
786 in 12 studies

Score = each part out of 100 × its weight. The weights are printed in “How we scored” below.

Why so many low grades? Most cinnamon studies are small, most used cassia, and doses ran from 120 mg to 6 grams. Our scoring marks that down, even when the result points the right way. The fasting number is different. It has the most people behind it, and now a 210-person study on true Ceylon ³.

So who is it for? People whose morning number is a little high before the next lab, people who already put cinnamon on their oatmeal, and people whose stomach did not get on with berberine. For them, Dosera's true Ceylon bottle, with coumarin at 0.1% or less is the safe version of what they already do. Here is each claim in full, starting with the morning number.

Every claim, scored

Lowers fasting blood sugar

C+62

Human studies · 45%70
Size of the effect · 35%60
Studies agree · 20%45

The best-supported claim, and the one most people buy cinnamon for. The morning number fell in most studies, though by different amounts.

This is the claim most people buy cinnamon for, and it has the most studies behind it. A 2013 review pooled 10 controlled studies with 543 people with type 2 diabetes. Fasting blood sugar fell by about 25 mg/dL on average ¹.

The catch is that the studies disagree a lot. Doses ran from 120 mg to 6 grams a day, and most used cassia, not Ceylon. A 2012 Cochrane review of 10 studies with 577 people called the fasting result inconclusive ².

The newest study did not use cassia at all. Owners often say the research only used cassia, and that was true for years. A 2025 study in Sri Lanka followed 210 adults with type 2 diabetes for 4 months. On a true Ceylon extract, both fasting blood sugar and A1c fell from where they started ³. The researchers hold a patent on that extract, so we want other teams to repeat it.

In people with prediabetes, a 12-week study gave 500 mg of cinnamon three times a day. Fasting blood sugar rose in the placebo group and stayed flat on cinnamon, a gap of 5 mg/dL ⁴. That is small, but it held up in a careful, placebo-controlled study.

Studies: [1], [2], [3], [4]

Lowers triglycerides and total cholesterol

C55

Human studies · 45%62
Size of the effect · 35%50
Studies agree · 20%50

Triglycerides and total cholesterol came down in pooled studies. LDL, the one doctors watch most, did not move for sure.

A 2017 review pooled 13 controlled studies with 750 people. Triglycerides fell by about 24 mg/dL and total cholesterol by about 14 mg/dL ⁸. LDL and HDL did not change by a clear amount.

Longer use did better than short use in that review. Dose did not seem to matter much. The 2013 diabetes review found a similar pattern, with triglycerides down about 30 mg/dL ¹.

An old 2003 study reported much bigger drops, up to 30% for triglycerides ⁵. In 2025 the journal added an expression of concern to that paper, so we gave it little weight.

Studies: [8], [1], [5]

Smaller after-meal spikes

C50

Human studies · 45%45
Size of the effect · 35%55
Studies agree · 20%50

A clear effect in a small study at 6 grams with the meal. At capsule doses, the evidence is thinner.

In a small Swedish study, 14 healthy adults ate rice pudding with and without 6 grams of cinnamon. With cinnamon, blood sugar rose less after the meal and the stomach emptied more slowly ⁷.

The 6 grams in that study is about five times what two capsules hold. So it is a real effect, but at a big dose. In the prediabetes study, 1,500 mg a day for 12 weeks lowered the 2-hour number on a glucose drink test compared with the start ⁴.

Owners report this one often on their meters: "my blood sugar doesn't spike so much when I eat treats." We score it in the middle because the studies are small.

Studies: [7], [4]

Lowers A1c

D47

Human studies · 45%66
Size of the effect · 35%30
Studies agree · 20%35

Mixed. Two studies found a drop, but the pooled reviews did not. Do not expect your A1c to move much on cinnamon alone.

A1c is the number your doctor tracks, so we were strict here. The 2013 review of 543 people found no clear change in A1c, about 0.16 points ¹. The Cochrane review found no difference either ².

Two single studies did better. In a 3-month study of 109 adults with an A1c above 7, 1 gram a day lowered A1c by 0.83 points ⁶. Usual care alone lowered it by 0.37 points. The Sri Lankan Ceylon study also reported a drop from baseline over 4 months ³.

Our reading: a small A1c change is possible, and a big one is unlikely. In the first months, your morning number is the better thing to watch. This is the claim many owners count on, and it scores lowest of the three blood sugar claims.

Studies: [1], [2], [6], [3]

Lowers blood pressure

D45

Human studies · 45%55
Size of the effect · 35%35
Studies agree · 20%40

A few points at most, and the reviews do not agree on the top number.

One 2020 review of 9 studies with 641 people found the top number fell about 5 points and the bottom number about 3 points ⁹. The effect showed up mainly in studies longer than 8 weeks.

A second review of 8 studies with 582 people found no clear change in the top number. The bottom number fell by about 1 point ¹⁰. That is too small to notice on a home cuff.

Studies: [9], [10]

Antioxidant and inflammation markers

D42

Human studies · 45%45
Size of the effect · 35%35
Studies agree · 20%45

Lab markers moved in small studies. Nobody has shown that you would feel a difference.

A 2020 review of 12 studies found cinnamon lowered C-reactive protein (a blood marker of inflammation) and raised total antioxidant capacity ¹¹. Doses ran from 1.5 to 4 grams a day.

These are blood markers, not symptoms. We scored the claim low because a better lab number here has not been tied to anything you would notice.

Studies: [11]

PCOS: cycles and insulin

D37

Human studies · 45%30
Size of the effect · 35%45
Studies agree · 20%40

Two small studies with promising results. Too few women to be sure.

In a 6-month study at Columbia University, 45 women with PCOS took cinnamon or a placebo. Periods came more often on cinnamon, but only 17 women finished all 6 months ¹².

In a 12-week study of 66 women with PCOS, 1.5 grams a day lowered fasting insulin and a measure of insulin resistance compared with placebo ¹³.

If PCOS is your main reason, inositol has more studies behind it. See the inositol guide.

Studies: [12], [13]

Body weight

D36

Human studies · 45%50
Size of the effect · 35%12
Studies agree · 20%45

About 2 pounds over several months in pooled studies. Not a reason to buy it.

A 2020 review of 12 studies with 786 people found an average drop of about 1 kg, a little over 2 pounds ¹⁴. That is a small change over months.

We scored it near the bottom on purpose. This is not what cinnamon is for. Next is the worry owners raise most: is cinnamon safe for my liver?

Studies: [14]

See the bottle these steps are for: Dosera Ceylon Cinnamon 1,200 mg »

Is Ceylon cinnamon safe for my liver? Side effects and coumarin

Thin layered Ceylon quills next to thick hard cassia sticks on a wooden board — Left, Ceylon: many thin layers. Right, cassia: one thick layer.

The main safety question with cinnamon is coumarin, a natural compound that can harm the liver in high amounts. European food safety experts set a safe daily limit of 0.1 mg per kg of body weight ¹⁵. For a 150-pound adult, that is about 6.8 mg a day.

One teaspoon of cassia a day can pass that limit for a 150-pound adult. In one test of 60 shop samples, cinnamon held 2,650 to 7,017 mg of coumarin per kg ¹⁶. That is about 2.7 to 7 mg in every gram, and a level teaspoon weighs about 2.6 grams.

True Ceylon is different. A US lab found only traces of coumarin in Cinnamomum verum bark, and substantial amounts in all three cassia types ¹⁷. So the label matters more than the brand name.

The bottle we'd buy states coumarin at 0.1% or less. Even at that ceiling, two capsules hold at most 1.2 mg, under a fifth of the limit for a 150-pound adult. A teaspoon of cassia can hold 7 to 18 mg. The other side effects owners report are milder: heartburn, cinnamon burps and an upset stomach when taken without food.

One case report describes liver trouble in a woman taking a cinnamon supplement with a statin ¹⁹. It is one case, but if you take a statin or have liver disease, ask your doctor first. If it is safe for you, the next question is how much to take.

Take it with food. Owners who took it on an empty stomach report most of the heartburn.
Split the dose: one capsule with breakfast and one with dinner.
If you get cinnamon burps, take it in the middle of the meal, not before.
If you use insulin or a pill like glipizide, check your meter more often for the first 2 weeks.
Stop and call your doctor if your skin or eyes turn yellow, or you have pain on your upper right side.

How much Ceylon cinnamon should you take, and when?

"I couldn't find how much I should take," one owner wrote, and many say the same. The studies used anything from 120 mg to 6 grams a day ¹. Most capsule studies sat between 1 and 2 grams. Two capsules of the bottle we'd buy give 1,200 mg, inside that range.

Owners who saw a change say the same thing: take it every day and do not skip. "Keeps me of meds. Must be consistent," one wrote. The dose is simple. Getting the real thing is harder, so here are the traps.

1With breakfast
Take one capsule in the middle of the meal with a full glass of water.
2With dinner
Take the second capsule with your evening meal, the one with the most carbs.
3Every morning
Write down your fasting number for 4 weeks so you can see the trend, not one reading.
4At 3 months
Take your log to your A1c recheck and show your doctor.

Before you buy Ceylon cinnamon anywhere: 6 warnings

You can buy Ceylon cinnamon anywhere. Most bottles we looked at fail at least one of these.

1"Cinnamon" on the label, cassia in the bottle
Only 39% of samples sold as cinnamon in one market check were true Ceylon ¹⁸. Most cinnamon sold in the US is cassia, and the label rarely says so. "Unreputable sellers will sometimes sell regular cinammon as Ceylon Cinnamon," one owner warned. The bottle we'd buy names the species on the label: Cinnamomum verum.
2Ceylon on the front, no coumarin number anywhere
The coumarin number is how you know a Ceylon bottle is safe to take every day. Cassia in one test held 2,650 to 7,017 mg per kg ¹⁶. "'Ceylon' on a Facebook ad is a claim rather than a certification," one owner wrote. Dosera states coumarin at 0.1% or less, so two capsules hold at most 1.2 mg.
3The serving-size trick
"1,200 mg" in big print often means a serving of two or three pills. "Please note that these are 600 mg capsules. Product label in amazon is misleading," one buyer wrote. Cheap 500 mg bottles need four pills a day to reach a study dose. Its label states 600 mg in each capsule, two a day, 1,200 mg in all.
4Oil softgels and "complex" blends that hide the cinnamon
Some ad softgels are mostly oil. "Mine had no Cinnamon only oil," one buyer wrote after cutting one open. Blends with ten herbs never say how much cinnamon is inside. Dosera lists every mg: 1,000 mg bark powder, 200 mg 10:1 extract and 200 mcg chromium.
5Cinnamon with no testing behind it
The FDA has warned about lead in several ground cinnamon brands. "Please please PLEASE make sure your buying cinnamon that has been tested and does not contain lead!!!" one owner wrote. Dosera says every batch is lab-tested.
6Video ads, bought reviews and refunds you never get
"I paid 400.00," one buyer wrote after a long video ad. Another said, "they give you the run around to get their 60 day guarantee." Reviews can be bought too, which is why the FTC banned fake reviews in 2024 ²². The bottle we'd buy shows the full price before you pay, and its 30-day guarantee needs nothing sent back.

See how Dosera Ceylon Cinnamon 1,200 mg handles every one of these »

Is my bottle really Ceylon? How to tell it from cassia

Real Ceylon smells milder than the jar in your cupboard, not stronger. Its quills are thin and papery, rolled in many layers, and they crumble in your fingers. Cassia sticks are one thick, hard layer, darker and redder. Powder is harder to judge, so the label has to do the work, and these are the six checks we used.

1The Latin name is printed
Cinnamomum verum or zeylanicum is Ceylon. "Cinnamon" alone usually means cassia.
2A coumarin number is given
This is the liver number. A real Ceylon maker has no reason to hide it.
3Honest milligrams
Mg per capsule and capsules per serving both clear, with no "equivalent" math.
4Real bark powder
Open a capsule. You should see tan powder and smell mild, sweet cinnamon, not oil.
5Every batch lab-tested
After FDA lead warnings on several ground cinnamon brands, testing matters more.
6Full price up front, money back
No cheap trial bottle that turns into a bigger bill, and a refund you do not have to fight for.

Grocery-store cinnamon jar
Almost always cassia. One teaspoon a day can pass the coumarin limit.
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"Cinnamon" capsules, no species named
Often 500 mg capsules where a serving is 2 to 4 pills. Usually cassia.
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Cassia sold as "cinnamon complex"
A blend with chromium and other herbs. You cannot tell how much cinnamon is in it.
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Ceylon capsules with no coumarin number
Probably fine. But you are taking the liver question on trust.
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- 4
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Cinnamon gummies
A few hundred milligrams and added sugar, for people watching their sugar.
- 1
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Ceylon softgels from Facebook ads
Mostly oil, "equivalent" milligrams, and complaints about monthly charges.
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Dosera Ceylon Cinnamon 1,200 mg
Dosera's bottle: true Ceylon (Cinnamomum verum), coumarin 0.1% or less, 600 mg in each of 2 capsules.
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Check price »

What you find on the shelf	Check 1	Check 2	Check 3	Check 4	Check 5	Check 6
Grocery-store cinnamon jarAlmost always cassia. One teaspoon a day can pass the coumarin limit.
"Cinnamon" capsules, no species namedOften 500 mg capsules where a serving is 2 to 4 pills. Usually cassia.
Cassia sold as "cinnamon complex"A blend with chromium and other herbs. You cannot tell how much cinnamon is in it.
Ceylon capsules with no coumarin numberProbably fine. But you are taking the liver question on trust.
Cinnamon gummiesA few hundred milligrams and added sugar, for people watching their sugar.
Ceylon softgels from Facebook adsMostly oil, "equivalent" milligrams, and complaints about monthly charges.
Dosera Ceylon Cinnamon 1,200 mgDosera's bottle: true Ceylon (Cinnamomum verum), coumarin 0.1% or less, 600 mg in each of 2 capsules.Check price »

One owner put the best test in one line: "Cut a capsule open and see what is inside." Do that with any bottle you buy, including ours. Ceylon powder is light tan and smells sweet and mild. Cassia is darker and hotter.

Of the shelf types above, only the bottle we'd buy passes all six. See the label for yourself and compare it with the one in your cupboard. A good label is half the story. The other half is the seller behind it.

The maker we picked

Why we picked Dosera's Ceylon cinnamon

We did not pick a famous name. We picked the bottle that matches the studies and passes every label check above. It is the only bottle we found that names the species, states a coumarin number and gives honest milligrams. See the Ceylon label.

True Ceylon at a studied dose
True Ceylon (Cinnamomum verum), with coumarin at 0.1% or less, as the label states. 1,200 mg a day in 2 capsules, inside the range most capsule studies used.
Every mg listed, no blend
1,000 mg bark powder, 200 mg 10:1 bark extract and 200 mcg chromium. No proprietary blend and no "equivalent" math.
Every batch lab-tested
Dosera says every batch is lab-tested.
Money back, nothing to send back
30 days from delivery. If it does nothing for you, you get your money back and do not ship anything back.
Rated by real buyers
4.8 from 1,764 reviews on Dosera's page.
Sold direct
Free US shipping, the full price on the page before you pay, and no cheap trial bottle that turns into a bigger bill.

Where to buy it: Buy it on Dosera's own site, where the $17.50 price and the guarantee apply. A listing anywhere else is not Dosera's and is not covered.

Check Dosera’s price →

Dosera's Ceylon cinnamon: what you get, and the downsides

Dosera Ceylon Cinnamon 1,200 mg

1,200 mg true Ceylon cinnamon (Cinnamomum verum, bark + 10:1 extract) and 200 mcg chromium in 2 capsules a day

★ 4.8 from 1,764 reviews on the maker's page

We picked one bottle for this page. It is true Ceylon, the label names the species, and it states coumarin at 0.1% or less. Two capsules give 1,000 mg of bark and 200 mg of 10:1 extract, plus 200 mcg of chromium.

It answers the two questions owners ask most: is it really Ceylon, and what about my liver? Two capsules give a dose inside the range most capsule studies used. If your morning number is a little high, Dosera's bottle is where we would start. Our view is one view, so here is what cinnamon owners say.

What it gets right

True Ceylon (Cinnamomum verum), not cassia
Coumarin 0.1% or less, printed
1,200 mg in 2 capsules a day, 60 capsules, 30 days
Supports healthy blood sugar levels already in the normal range
200 mcg chromium in the same 2 capsules
Lab-tested every batch
4.8 from 1,764 reviews on the maker's page

What to know

Cinnamon's studies are smaller and more mixed than berberine's. If your readings sit in the 200s, it will not be enough on its own.
Two capsules every day. Owners who skipped days say their numbers crept back.
A strong cinnamon smell when you open the bottle, and some people burp cinnamon.
It takes 2 to 4 weeks to show on a meter, and 3 months to show on an A1c.

An opened Ceylon cinnamon capsule spilling light tan powder beside the bottle — Open one. It should look and smell like real cinnamon.

A man in his sixties taking a capsule with breakfast at his kitchen table — One capsule with breakfast, one with dinner.

Who should not take it

Anyone on insulin or a pill like glipizide who has not talked to their doctor first (risk of lows)
People taking warfarin or another blood thinner, unless their doctor agrees
Anyone with liver disease, or taking a statin, without asking their doctor
Pregnant or breastfeeding women
Anyone allergic to cinnamon
Children

$17.50 a bottlefree US shipping

Sold direct by Dosera · 30-day money-back guarantee, nothing to send back · free US shipping

Did cinnamon work for other owners?

These are real comments from owners of many different cinnamon products, not this bottle. We kept the ones that did nothing too.

“Had to actually be the ceylon cinnamon though, cassia bark cinnamon had no effect at all”
r/diabetes_t2 member

“My fasting blood sugar readings are getting better. Hopefully, it will continue to improve. I've only been taking the capsules for two weeks”
Store reviewer, true Ceylon capsules

“I've been taking two 500 mg capsules each morning for a couple months now and am not seeing any benefit”
TuDiabetes forum member

“I believe this helped my blood sugar not spike as high after carb heavy meals”
Walmart reviewer, cinnamon capsules

“my fasting readings are down 20-30 points. I will watch with interest”
Store reviewer, true Ceylon capsules

“I noticed when taking cinnamon previously, I would be sick to my stomach afterwards. I do not have that when taking Ceylon cinnamon”
Amazon reviewer, Ceylon cinnamon capsules

“I make certain to take CEYLON cinnamon rather than regular cinnamon as Ceylon cinnamon is safer for one's liver”
Mayo Clinic Connect member

“One after breakfast and one after supper splits the dosage so that the cinnamon doesn't upset my stomach”
iHerb reviewer, Ceylon cinnamon 600 mg capsules

“I'm using it in hopes of avoiding having to take a medication. Fingers crossed”
iHerb reviewer, Ceylon cinnamon 600 mg capsules

“cinnamon burps are better than fish oil burps!”
TuDiabetes forum member

Not the right one for you? Four other options

Berberine

Dosera Berberine HCl 1,200 mg + Ceylon Cinnamon

Larger studies and bigger drops in blood sugar. Take it with food, because it can upset the stomach at first.

Inositol

Dosera Myo + D-Chiro Inositol 40:1

The best-studied pick for PCOS and insulin resistance. Four capsules a day.

Alpha-lipoic acid

Dosera Alpha-Lipoic Acid 600 mg + Benfotiamine

For pins and needles and the fire in your feet at night. Not mainly a blood sugar pick.

Gymnema

Dosera Gymnema Complex

For sugar cravings after meals. One capsule with each meal.

Dosera true Ceylon cinnamon, coumarin 0.1% or less, 1,200 mg a day · $17.50 a bottle

Sold direct by Dosera · 30-day money-back guarantee, nothing to send back · free US shipping

When will I see a difference? Week by week

A paper log of morning blood sugar readings next to a meter and a coffee mug — Write down the morning number. Trends tell you more than one day.

1Days 1 to 7
Nothing on the meter yet
This is normal. Take it with food and watch for heartburn. Most people notice only the cinnamon smell.
2Weeks 2 to 4
The morning number may start to drift
Remember the reviewer stuck at 115 to 130 in the morning? Another owner on Ceylon capsules wrote: "When I started, my fasting blood sugar was 127. This morning it was 114." Not everyone sees that, and the 30-day money-back guarantee covers it.
3Weeks 6 to 8
Check your trend
Compare your 4-week averages, not single days. Owners say skipped days show on the meter. If nothing has moved, ask your doctor about a next step.
4Month 3
The A1c recheck
Take your log to the doctor. The studies point to a small A1c change, if any. Here is how we scored those studies.

How did we score the claims?

We searched PubMed for human studies on cinnamon and each claim. We used pooled reviews first, then the largest single studies. We read the abstracts and recorded the dose, the length and the number of people.

Most cinnamon studies used cassia. Where a study used true Ceylon, we say so. We cut scores where results came from one small study, where the journal raised concerns, or where the researchers had a financial interest.

We also read 673 comments from cinnamon owners on Amazon, Walmart, iHerb, WebMD, Reddit and diabetes forums. They shaped the questions, not the scores. They also raised the price question: why not the cheap jar?

Human studies only. No lab dishes, no mice.
Units are US: mg/dL for blood sugar, A1c in % points.
Every number links to the paper it came from.
Owner comments came from many products, never this bottle.

The weights

Human studies45%
How many people were studied, in how many controlled studies, and how good those studies were. Lab and animal work counts for nothing here.
Size of the effect35%
How much the number moved in people, in units you would see on a meter or a lab printout. A change you could not notice scores low.
Studies agree20%
Whether most studies point the same way. Cinnamon studies often disagree, so this part pulls several scores down.

What we did not score

We did not score lab studies that call cinnamon "insulin-like". They are done in dishes, not people. We did not score taste or smell. We also did not score the chromium in the bottle as a separate claim, because this page is about cinnamon.

Why not the $8 jar of grocery-store cinnamon?

A cheap jar of ground cinnamon next to a supplement bottle on a kitchen counter — The cheap jar is cassia. The cost shows up as coumarin.

The $8 jar can cost your liver more than it saves you. One owner paid "less than $8.00" for two bottles of cassia at Kroger. Cheap cinnamon is almost always cassia, and a teaspoon a day can pass the coumarin limit for a 150-pound adult ¹⁶.

At the other end are the ad bottles. Owners describe paying up to $60 a month for softgels, and some multi-bottle blood sugar orders run $400. "I paid 400.00," one buyer wrote after watching a video. Another wrote, "I just wanted the first order and it's an automatic shipment whether I want it or not."

Dosera's bottle is $17.50 a bottle, with free US shipping. That is no more than most Ceylon bottles we found that fail a label check, and far below the ad softgels. The 30-day money-back guarantee needs nothing sent back. Check the label and price before you decide, but first, what happens if you do nothing.

What happens if you wait?

An older couple reading a lab results letter together at the kitchen table — Most people with prediabetes find out from a letter like this.

Eight in 10 Americans with prediabetes do not know they have it. The CDC puts the total at 115.2 million adults, more than 2 in 5 ²⁰.

In the large US Diabetes Prevention Program, people with prediabetes who got a placebo developed type 2 diabetes at about 11 per 100 people each year ²¹. A program of eating changes and about 150 minutes of activity a week cut that risk by 58%.

So food and walking matter most. As one owner put it, "You still have to do a little exercise to maintain good results." Two capsules with meals is the easy daily part you can keep up while you work on the rest. Below are the questions owners ask us most.

A supplement is not a substitute for medicine. Ceylon cinnamon will not replace a prescription, and you should keep your doctor in the loop about anything you take. Talk to your doctor if you take medicine for blood sugar. If anyone promises that a cinnamon capsule will replace your prescription, walk away.

Dosera true Ceylon cinnamon, coumarin 0.1% or less, 1,200 mg a day · $17.50 a bottle

Sold direct by Dosera · 30-day money-back guarantee, nothing to send back · free US shipping

The analyst who disagreed

I would score after-meal spikes lower. The one clean study used 6 grams with a pudding, five times what two capsules hold. A 10-minute walk after dinner costs nothing, and you can watch it work on a meter that same night. Take the cinnamon if you like it, and add the walk.

Marcus Bell · Fitness & Nutrition analyst

Questions people ask

Is Ceylon cinnamon better than regular cinnamon for blood sugar?

For the liver, yes. Ceylon has only traces of coumarin, while cassia carries 2,650 to 7,017 mg per kg ^16,17. For blood sugar, most older studies used cassia ². But a 2025 study of 210 adults found a true Ceylon extract lowered fasting blood sugar and A1c over 4 months ³. So you no longer have to choose between the studied kind and the safe kind.

I take metformin or insulin. Can I take Ceylon cinnamon?

Talk to your doctor first. Cinnamon can add to the effect of blood sugar medicine, and with insulin or a pill like glipizide that can mean lows. If your doctor agrees, check your meter more often for the first 2 weeks. Never stop or cut a medicine on your own.

How long until I see a difference?

Owners who saw a change usually saw the morning number drift down in 2 to 4 weeks. A1c takes 3 months to show anything, because it reflects about 3 months of blood sugar. Some people see no change. If that is you in the first 30 days, the money-back guarantee covers it, with nothing to send back.

What are the side effects of Ceylon cinnamon?

Most people have none. The common ones are heartburn, cinnamon burps and an upset stomach when taken without food. Some people are allergic to cinnamon. True Ceylon has very little coumarin, so the liver worry with cassia mostly does not apply. Take it with meals and split the dose.

Can I take Ceylon cinnamon with berberine?

Yes, many people do. The berberine bottle we recommend already includes 100 mg of Ceylon cinnamon extract, so you may not need both. If your numbers are only a little high, start with cinnamon alone. If you have PCOS, cinnamon and inositol can be taken together. Ask your doctor if you take blood sugar medicine.

Why not just buy a cheaper Ceylon cinnamon on Amazon?

You can, but check it first. Many bottles print "1,200 mg" for a serving of two or three pills. Many say "cinnamon" with no species, which usually means cassia. Many Ceylon bottles give no coumarin number at all. And some reviews are bought; the FTC banned fake reviews in 2024 ²². Dosera's bottle is $17.50 a bottle, passes all six checks and comes with a 30-day money-back guarantee with nothing to send back. Compare the label yourself.

How do I know a bottle is really Ceylon?

Read the label for Cinnamomum verum or Cinnamomum zeylanicum. Look for a coumarin number. Then open a capsule. Ceylon powder is light tan and smells sweet and mild. Cassia is darker, redder and hotter. If you buy sticks, Ceylon quills are thin and papery in many layers; cassia is one thick, hard layer.

Is a teaspoon from my spice jar the same thing?

Only if the jar says Ceylon. A level teaspoon is about 2.6 grams. If it is cassia, that teaspoon holds roughly 7 to 18 mg of coumarin ¹⁶. The safe daily limit for a 150-pound adult is about 6.8 mg ¹⁵. A sprinkle on oatmeal is fine. A daily teaspoon of cassia, every day for months, is not.

Our verdict

If your A1c is above 8, or your readings sit in the 200s, cinnamon is not enough. See your doctor, and read the berberine guide, which has much stronger studies. Cinnamon will not close that gap.

Ceylon makes sense if your morning number is only a little high, if berberine upset your stomach, or if you already use cinnamon daily. If you are like the reviewer stuck at 115 to 130 in the morning, the fasting number is where the studies point. True Ceylon lets you take it daily without the coumarin worry.

Do not take our word for it. Next time you are in the spice aisle, pick up any cinnamon and look for three things: the Latin name, a coumarin number and the mg per capsule. Most of the shelf types in our label check miss at least one. Dosera's bottle prints all three.

If you take cinnamon every day, make it true Ceylon with the coumarin printed on the label.

The bottle we'd buy · Dosera

Dosera Ceylon Cinnamon 1,200 mg: true Ceylon, coumarin 0.1% or less

★ 4.8 from 1,764 reviews on the maker's page

True Ceylon (Cinnamomum verum), not cassia
Coumarin 0.1% or less
1,200 mg plus 200 mcg chromium in 2 capsules a day
60 capsules, 30 days, lab-tested every batch
$17.50 a bottle, free US shipping
30-day money-back guarantee, nothing to send back

$17.50 a bottlefree US shipping