Doctor's Note

The Antioxidants in a Pinch video I’m so proud of can be found here. The Safer Cinnamon is where I originally brought up the coumarin issue. What about the Oxalates in Cinnamon? Not a problem, but the oxalates in too much turmeric may be a concern. Superfood Bargains is where I ranked foods in terms of antioxidants per unit cost.

I talk more about the potential potency of plants in general in Power Plants and more about spices in particular in videos such as:

Amla Versus Diabetes explores the use of Indian gooseberries as a way to help control blood sugar, though the best way to deal with diabetes is to prevent and treat it with a healthy diet. Books I would recommend (in order of publication) are Defeating Diabetes, Dr. Neal Barnard’s Program for Reversing Diabetes, and The End of Diabetes.

As you’re making your Healthy Pumpkin Pie, don’t accidentally add too much nutmeg, the subject of my next video Don’t Eat Too Much Nutmeg.

For more context, check out my associated blog posts:  Cinnamon for DiabetesNutmeg Toxicity, and Tarragon Toxicity?

If you haven’t yet, you can subscribe to my videos for free by clicking here.

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  • Brian Humphrey

    Thanks Dr.Greger for the brain nutrition! Love it!

  • Ilana

    I don’t get it – how are we supposed to know which cinnamon we have and how do we buy the right one?

  • RuthSC

    What effect does Saigon cinnamon (on every grocery store’s shelves of spices bearing the McC brand) have compared to Cassia and Ceylon varieties?

    • John B

      I’d like to know the answer to this one too. I was using Saigon cinnamon before Dr. Greger’s earlier video which recommended Ceylon cinnamon, and I prefer the taste of the Saigon cinnamon available and Costco.

    • Mack

      Here’s your answer John, and I’m afraid it’s not good news; Saigon cinnamon is relatively high in coumarin.

      • John Smith

        Thanks Mack. I won’t be using Saigon any longer.

        • Marilyn

          Tim Ferris tested all three by wearing a continuous glucose meter in his side so he could tell what his blood sugar was doing after everything he consumed. This is what he found:

          “I tested three species of cinnamon as powders for glycemic index (GI) response: Ceylon cinnamon (Cinnamomum verum or zeylanicum, also referred to as “true cinnamon”), Cassia cinnamon (Cinnamomum cassia or aromaticum), and Saigon cinnamon (Cinnamomum loureiroi, also known as Vietnamese cinnamon).

          Though Cassia is thought inferior to Ceylon or completely ineffective in some bodybuilding circles, it has lowered glycemic response in both published studies and in my experience. This is fortunate, since Cassia is what is most often found at coffee shops and restaurants if you ask for
          “cinnamon.” I found Saigon cinnamon to be most effective, with Cassia in close second place and Ceylon in much further third place.”

          Dr. Amen also looks at scans of brains all the time and he recommends cinnamon, so it can’t be that bad. I’m going to stick with the Saigon, since I bought a pound of it on iherb. If anyone needs a coupon, PEY 561 works.

  • How does 1 teaspoon of cinnamon compare to OTC capsules dosed in mg? Are the OTC capsules usually cassia or ceylon?

  • How do you know which cinnamom you are getting? If I am buying organic does that make a difference? Thanks Dr. G..You are helping me save my life—really…THANK YOU! Lisa O in NJ

    • Marilyn

      I bought Saigon cinnamon specifically at iherb. See my post above for Tim Ferriss’ results of all three cinnamon types.

  • Thea

    For those who are asking about what kind of cinnamon you are getting, you can order the ceylon from on-line if you want to be sure. I got mine from Amazon after watching one of Dr. Greger’s earlier videos.

  • Thea

    QUESTION: The video gives an awesome history an explanation of why the safe cinnamon is not likely going to help with diabetes problems. However, video goes on to say that cinnamon has other great properties, so it is still worth it integrate ceylon into our diet.

    Well, just as past diabetes research focused on cassia, doesn’t it seem likely that past research on other benefits of cinnamon also focused on cassia? So, how do we know which, if any, benefits that ceylon has?

    • Toxins

      The major benefit Dr. Greger is referring to is the antioxidant content which remains quite high.

      • Thea

        Thanks Toxins!

  • Kim

    What if you are consuming 1-2 cups of spinach per day? Would you recommend reducing or not consuming turmeric? (I am considering taking a turmeric supplement to help arthritic pain.)

  • dimqua

    What about eating a two teaspoons of cassia every two days? This can be harmful for adults?

    • R Ian Flett

      The recommended maximum consumption of ground Cassia for liver toxicity is half a teaspoon a day based on some sources. However, as the video suggests, that may also be too little to get the insulin sensitivity benefits. We really need more research.

      • dimqua

        Therefore, is it ok to eat a teaspoon of cassia three times a week or less?


  • Plantstrongdoc

    I guess no surprise. No magic “pill” in nature either. Cinnamon and SAD will not improve your health, if you have type 2 diabetes, nor metformin and SAD. Changing your diet to a low fat, plantbased diet, and moderate exercise will surely improve your health, maybe even cure type 2 diabetes.

    • Marilyn

      Why do so many people target fat instead of sugar in diabetes? Sugar is the culprit, healthy fats are necessary for health.

      • Thea

        re: “Why do so many people target fat instead of sugar in diabetes?”

        Because the best studies show that sugar does not cause diabetes. Sugar problems are a symptom of diabetes, not the cause. If you want to learn more about the cause of diabetes, I highly recommend the book: “Dr. Neal Barnard’s Program For Reversing Diabetes.” Dr. Barnard’s plan is 3 times more effective than other diet plans and he stresses truly low-fat.

        re: “…healthy fats are necessary for health.”

        While this sounds logical on the surface, “the devil is in the details.” Your statement would only be true depending on how you define healthy fats and at what amounts. Usually people who push “healthy fats” are actually pushing non-healthy fats (oils of one type or another) and amounts that are way too high. Plantstrongdoc’s word choice of “low-fat” is far more likely to lead someone in the right direction if they want to adopt a healthy diet.

        If you want to learn about what constitutes a healthy diet, you are in the right place. Keep watching more videos here. Also, check out the PCRM 21 Day Kickstart program. Good luck.

  • John

    so Saigon cinnamon is no good either?

  • R Ian Flett

    If you look carefully at the picture of the two types of quills you will note that the Ceylon variety curls in from both edges, whilst the thicker, woodier and darker, Cassia scrolls only from one edge to form a single spiral. The Ceylon variety also usually has more inserted inside each scroll and often has frayed ends. Because the Cassia is much cheaper you are more likely to find it used for the ground cinnamons, so unless the packaging specifically mentions Ceylon, then, as Dr Greger suggests, assume that its the cheaper and potentially toxic Cassia. If it’s origin is China or Indonesia, then it’s Cassia.

    It used to be thought that cinnamon was high in chromium, which helps in glucose control, but this may be due to the association of cinnamon supplements that also contained chromium picolinate that were popular quite a while back, but were later discredited as weight loss supplements. In the Cassia type it’s still uncertain as to whether it’s certain polyphenols or the coumarin that’s improving insulin sensitivity.

    Keep your cinnamon, especially the powder, in the fridge as it does go off.

    I use a Ceylon cinnamon stick with cloves in my water jug to create an infused water for my teas and coffee. Beware that the second boiling will violently boil over due to the cloves reducing surface tension. You can keep adding water for a day or two, but only reheat to below boiling.

    • Thea

      re: “Keep your cinnamon, especially the powder, in the fridge as it does go off.”

      That’s a great tip! When I bought the ceylon from the web, it came in a pound bag – really a LOT for what I need. I’ve only used a tiny fraction of it, and it’s sitting in my cupboard. I wonder if it’s gone bad by now? Do you know how to tell? I had thought that it might loose potency over time, but I hadn’t considered it going “bad”.


      • R ian Flett

        Apparently, as it goes off, it loses much of its typical aroma.

  • Pat

    You can buy a pound of organic Ceylon cinnamon at for less than the price on And if you use code POD782, you can get another $5 or $10 off, depending on the size of your order. Also, click on “freebies” at the top of the page, and you can select a free sample of something.

  • William

    I read that cinnamon extract with Cinnulin PF can give you the benefits of cassia cinnamon without the coumarin, because it is the water soluble form of cassia which does not contain the coumarin, the latter residing in the dry portion of the spice.

  • Mo jean

    Thanks for cutting thru the clutter. Now I know why I purchased Ceylon and left Cassia on the shelf.

  • Ale Flechas

    Thanks Dr. for all your advice, I’m Ale I’ve been diagnosed with Polycystic ovary syndrome (PCOS) my dad has diabetes type 1, I was tested for hypoglycemia and was found to be positive, as well as high cholesterol, I didn’t expected my test to have those results as I try to eat really healthy exercising couple of times a week, I’m taking my pills in halfs (850g) Metformin at lunch and dinner, I’m also taking birth control pills to regulate my period, I also suffer from constipation. I wonder if you’ve got any advice??? many thanks

    • SFChutzpah

      Nothing is better for constipation than oven roasted sweet potatoes. Really. :)

    • kara

      I have to recommend being tested for celiac disease/gluten sensitivity. All your symptoms point to it. I also suffer from celiac and had major hormones issues atop constipation, etc…

  • Carlo

    Looks likey C. loureiroi and C. burmannii are dangerous as well:

  • Ingrid Du Preez-Japp

    Thank you Dr. Greger! Due to having given my husband and I this important information, I am now about to order my first bag of Ceylon Cinnamon! May God bless you! :))

  • SFChutzpah

    When my doctor told me my blood sugar level was too high, I started using cinnamon (in bulk, sprinkled on steel cut oats) from the Rainbow Grocery here in San Francisco. Whatever kind of cinnamon it was, it certainly worked beautifully. The Rainbow Grocery is just of of those stores you trust, so I’m sure it was fine.

  • Majo

    would anyone know what type of cinnamon is most commonly found in México? or is it possible to be able to identify ceylon from Cassia cinnamon when not int powder but in stick? … thanks!

    • Eric

      There is a simple test for distinguishing between Cassia and Cinnamon. Take a pinch of the powdered herb and apply a small drop of tincture of iodine. If the powder turns blue or purple, it is Cassia. The iodine will have very little affect on Ceylon Cinnamon.

  • Ready to seek psychiatric help

    Here in lies the problem with why people turn away from health and diet. One day something is good for you or causes cancer and the next its totally new information. I have joined a really good gym and am doing High Intensity Interval Training. The membership came with an hour with a “Nutritional Expert”. Our meeting ended 2 hours and 15 minutes later…:) They pounded in to me that I was to eat Eggs, Butter and red meat and vegetables every day and that all the research has shown that in fact sources were wrong with cutting these staples out. They have up on the wall the cover I think to Time Magazine with show a scoop of butter and says “Butter is Back”. I was making a shack every day with 50 grams of Acai berry pulp, One stick of cinnamon, half a cup of blueberries, half a cup of cranberries and one cup of Kefer. Do I cut the cinnamon out now? I eat a cup of steel cut oats every morning with 50 grams of walnuts and a banana. The “nutritional Expert” says if I do not stop eating oatmeal I will make no gains no matter how hard I work out. Do you see where I am going with this? Google is butter good for you. Google are eggs good for you.

    • EviReed

      It’s always best to search for the information that is peer reviewed, scientifically backed, and not funded by someone with a vested interest. In my opinion, you won’t find better scientifically-backed information out there than what Dr. Greger puts together for us in his videos. If you’d prefer to look things up on your own, try PubMed, although it will be way more work for you than just coming here.

      Anyone can spout off any health/nutrition information they want and not have anything to back it up. Look at what happened with the Atkins Diet. You will also get nowhere fast just using Google unfortunately.

  • The cinnamon that is available here is usually locally grown. How do I know which variety it is and whether it belongs to one of the safe types?

  • jwisnie

    How do we know that coumarin is toxic to humans? I have problem finding studies, that proof this theory. There have been some studies on rats, but this is a very weak proof. Is it possible, that EFSA released their recommendation based on those papers?

  • H. Zayre

    People –please stop! If you have been using cinnamon for your diabetes and having good results, stick with it. Whether it is from Saigon or Zambodia! Don’t be blown about like leaves in the wind. This is a money-oriented blog. He is going to sell you what HE sells. Look at the links and ads. Watch his videos on YT which are crass and rude. The made is smart, but chiefly in the posterior! Stop it!

    • Thea

      H. Zayre: What ads? What links? There are no ads that I can see. And the only links/mention of purchases on this site are for a nutrition book or DVDs of these videos. In those cases, *all* of the proceeds go back to supporting this site. Not a single penny goes to Dr. Greger. Not one penny. The only purpose of this site is educating people on evidence based nutrition. Every video is eventually made free to everyone on this site. What has you so upset?

    • IMRightNURNot

      MINDLESS BLOWHARD alert ~~~^

  • Teresa

    you can buy the good cinnamon at most health food stores.

  • Sef24

    On the infographic of the four types of cinnamon, it shows cassia cinnamon with a red light (indicating a dangerous level of coumarin), Vietnamese and Indonesian cinnamon with a yellow light (indicating a cautionary level of coumarin), and Ceylon cinnamon with a green light (indicating a safe(er) level of coumarin).

    This seems to contradict what I’ve read before about coumarin levels in those types of cinnamon. From what I’ve read, cassia cinnamon contains 0.31 g/kg coumarin, Indonesian cinnamon contains 2.15 g/kg coumarin, and Vietnamese cinnamon (aka Saigon cinnamon) contains 6.97 g/kg coumarin. Whereas Ceylon cinnamon (aka Mexican cinnamon or True cinnamon) only contains 0.017 g/kg cinnamon. (

    Your info seems to say that Vietnamese and Indonesian cinnamon have the medium levels and cassia has the high level.

    Could you share your sources for which types have the greater presence of coumarin? I’ve been a Ceylon cinnamon advocate since I first read the article from the above link a couple years ago, but I understood Vietnamese cinnamon to be the most dangerous, with Indonesian cinnamon coming in behind Vietnamese cinnamon, and Cassia cinnamon after Indonesian cinnamon. Is that information incorrect? Does it have anything to do with different bioavailablities from the different sources or is/was there a mixup with the infographic?

    Thank you!

    I really enjoy this site and the presentation of yours I was able to attend last month in CA. I’m saturating myself with the info and videos from your site here and sharing them with family. So helpful and appreciated. Thank you!

  • Thank you doctor!! I have a question what’s the difference between this Cassia Cinnamon and the one from Thailand Burmannii? Are they the same type just named differently? And if they are different is the Burmannii safe? I have a half kilo pack now should I stop using it and buy just Ceylon?

  • Steve Y

    Can anyone tell me what “dose” steeping a 2″ cinnamon stick in a hot cup of tea equates to? I.e., number of teaspoons of ground cinnamon?

  • Viola

    Hello, I thought that the bioactive compound isolated from cinnamon which acts as a mimetic of insulin was first classified as a methylhydroxychalcone polymer (MHCP), and is not coumarin? The literature seem to cite this rather.. Does anyone know? Thanks

  • sinlou0911

    How many milligrams should you take per day of the ceylon?

    • sinlou0911

      In the video of his that I saw (which is what lured me here) he had a red light over cassia and a green light over ceylon, a yellow light was over saigon and one other but looks like in the comments, yal are saying ceylon is the least effective. SO, would you then take a higher mg of ceylon?