Q. I've always been susceptible to getting canker sores in my mouth so when I heard that kiwi fruit could make them go away quickly, I had to try. Wow! It was gone in 2 days.

I had another one about a week later and ate a kiwi. Again, my canker sore was gone in 2 days. Now I don't wait for the canker sore to show up. I just eat a kiwi every few days. I'm 58 and had suffered with canker sores since college.

A. Although we could find no scientific evidence that kiwi fruit helps heal canker sores, you are not the first to report this effect. Eight years ago a reader wrote, “I have suffered with mouth ulcers all my life. I have tried many home remedies, over-the-counter cures, and a few prescriptions. Eating one kiwi cures my canker sores as fast as the prescription steroid cream, and the kiwi doesn't come with warnings about the danger of putting it in your mouth. It has helped a few of my friends also.”

Other canker sore remedies include sauerkraut juice, powdered instant tea (or a wet tea bag), L-lysine, acidophilus and goldenseal.

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  1. Eric

    I’m the same, I also found this forum because I googled kiwi as a possible cause for canker sores. I don’t usually eat kiwi (and I don’t usually get canker sores) but just started recently and got a lot of sores in my mouth which hung around for along time. Eventually I decided to stop eating kiwi and now they seem to be going away.

  2. Clarke

    The reason I found this forum was because I googled Kiwi as a possible cause for canker sores. I have been eating them a lot lately and was wondering if they were the CAUSE of my canker sores, which I never really had a problem with in the past.

  3. Frank

    Well to start with I am 65 years old and have been dealing with canker sores all my life. I would say that there isn’t a day that goes by that I do not have one though they vary from very small to enormous. When I say enormous at the age of 25 they covered my tongue and the inside of my mouth so much that my tongue was entirely white. I could not eat or even talk during that episode for three days until a dentist prescribed xylocaine a local anesthetic. Xylocaine would numb my mouth and relieves the pain for about 5 to 10 min. at a time. This allowed me to at least continue eating.
    As you might guess over the years I have tried every remedy that anyone would suggest. I even changed my diet numerous times eliminating the things that are believed to cause canker sores. None have worked so when I heard about using Kiwi I thought I will give it a try. I have been eating one whole Kiwi every day for two weeks now. At this point it has done nothing. In fact some rather large ones have appeared in the past few days on my tongue and one at the gum line.
    I will continue eating them since I rather like them anyway. I am glad it is working for some people but I guess the rest of us will just have to suffer.

  4. CG

    I have ulcers on my tongue on either side that are so painful all I want to do is sleep. I have tried everything from prescriptions to changing my tooth paste, to different otc medications, and nothing seems to work. I have had these two ulcers for 10 years, and they used to go away every few weeks, but now I have them constantly they never get better, and never go away. I have had every doctor that I have contacted check them out, I even had them biopsied in 2004, 2005 they were examined by a Tufts University pathologist, to no avail. So now just what can I do?

  5. Basma

    I figured this out myself.. I get mouth ulcers since I was a teenager… I tried many stuff.. then one day I had a kiwi and thought of trying it too… it works like magic! from the first time of use, you find some change in size in the ulcer in the next day! It takes just 3 days and it starts to fade away completely and the pain is gone… I put a piece of it directly on the sore just one time a day for about 15 minutes… it stings so much at first then the sting vanishes..
    I tried to freeze the kiwi just in case I had the sore and I couldn’t find the kiwi, but it didn’t work! frozen kiwi don’t work like fresh ones!

  6. BJS

    Poking metal objects for 2.5 hours for my three cavity fillings let me with some pretty nasty sores. It’s 2:30pm and I’ve only been able to eat 1 slice of bread by itself. This isn’t the first time, and I’ve noticed that webmd has added some helpful stuff since I last checked: http://www.webmd.com/oral-health/guide/canker-sores Something to remember is that everybody’s bodies are different… which is why in every remedy (even scientific ones) people respond differently. I’ll try the 1/2 kiwi, what the heck!
    I’ve found many similar lists of what not to eat… any ideas of what to eat? So far I’ve got ice cream, yogurt, milk- basically straight up dairy.

  7. TMR

    I am suffering from two canker sores on my cheek and nothing seems to help. The pain was starting to get worse and I googled for pain relief. So, found this kiwi option and decided why not… grabbed my keys and went to the market. I finished my kiwi about five minutes ago and I can fully open my mouth now. The pain in my cheek is gone but I still have a little bit of a sore throat. I’m hoping that the pain stays away but if it does come back I will go pick up another kiwi.

  8. kc

    Well it works for me and might for other people so maybe you should figure the “us” is just your family.

  9. jasmine

    umm, i tried all the kiwi in my house and umm it didnt work for my canker sore so stop telling us it does ok.

  10. jasmine

    I hope this kiwi trick works. I just now got a canker sore and it hurts like hell. I tried salt water and everything so I sure hope this works!!!!!!

  11. tiffy

    I have never heard of this before but I get canker sores really bad, my whole mouth gets full of them. I have a couple now and just found this site because I was curious as to why my tongue was burning. If my canker sores are gone in the next few days the burning tongue will be worth it.

  12. LWR

    I don’t know what causes them (canker sores) I just wanted them gone. My son and granddaughter suffered with them also. Our remedy is as little as 1/2 kiwi once a week and they’re gone. My son and granddaughter split one, I eat a whole one. After many years, they are no more. Sometimes I feel one starting but it never develops and by the next day it’s gone.

  13. BH

    I understand the pain of canker sores and am annoyed that there is so little information available about them. It seems when I get them my whole mouth gets really sensitive to acid.. my tongue hurts from acid, my teeth even hurt (I haven’t worn my retainer in a few years after I’ve had braces) which is curious and the sore hurts very badly.
    Sometimes using a mouthwash would help, but other times it reactivates the canker sore (irritates it). Also lately I wake up with bad breath (something I usually don’t wake up with). Not sure why all these things are happening at once, but oh well.. I, too, would be afraid of eating a kiwi.

  14. jennifer

    Oh my god.. I have a canker sore right now and its so annoying. Everything I eat kills me. I have tried the salt water and nothing. I think I’m pretty scared to try the kiwis because I’m pretty sure I got this from pineapples and biting the inside of my cheeks. I need help fast!

  15. hlcamero

    This is so sad that eating kiwi is supposed to help… because I think eating too many kiwis, pineapples, and strawberries are what caused my (extremely painful and large!) canker sores :( I’m far too afraid to eat another kiwi… I don’t want to make it worse!
    Has anyone tried putting a wet black tea bag on the canker sore? I shoved one on the side of my mouth with the sores, left it there while playing cards with my family and it felt amazing…it didn’t heal it though, it just felt good (it has the chemical tannin which eases pain). My family still makes fun of me for how dumb I looked, but oh well, they don’t know my pain!

  16. DY

    I’m 25 and i just got my First canker sore and it was after i bit the inside of my lip really hard and made it bleed while taking a huge bite of food. i tried the salt water and nothing. Ill try the Kiwi today! wish me luck :)

  17. A.B.C

    I need a remedy for canker sores, they are so annoying.
    I’ve read remedies on the internet and I have not found much. I hope kiwi works!

  18. Sally

    One time I bit my lip and it became a huge canker sore the next day. It was so painful, I tried everything to get rid of it.
    -poured lysterine on it which helped it get smaller
    -gargled with salt water, three times a day
    -tried over-the-counter anbesol and oragel which really help to numb the pain. I’m still dealing with this canker sore and its been more than a week, but its much less painful. Only thing I haven’t tried is kiwi, hopefully that will work! I’ll keep you posted!

  19. Rob

    I gotta tell you – I’m anxious to try out this kiwi “therapy” and no SLS toothpaste right now. It’s kinda late to go shopping, though. I’ll do that first thing tomorrow :)
    Anyway, I get canker sores irregularly (on the average I’d say once per 2wks, I got one going on now) and I’m never sure what’s causing them. My observations are as follows:
    – accidental biting on the inside of the cheek/lip
    – drinking beer/poor diet?
    – no breakfast
    – eating junk food like barbecue potato chips
    I really hate them, I hate the pain, and the weird feeling when you touch the canker sore… It’s almost as if you were connecting + and – terminals on the 9V battery with your tongue.
    I’ll try kiwi and the new toothpaste and let u know the results.

  20. DrKoob

    I get canker sores whenever I eat anything that has Worcestershire sauce in it. Seriously. Has anyone ever had that problem and do you know what the contents of Worcestershire sauce are? I try to avoid it like the plague but restaurant chefs sneak it (or the ingredient I am allergic to) into food all the time.

  21. LB

    I had suffered with canker sores since I was a teenager and tried several home remedies and topical medications with no results. I’m 58 now.
    I tried to drink half a gallon of pineapple juice and it cleared my canker sores in a day or two.

  22. christy

    I had to stop eating dried fruit. For some reason, it made me susceptible to canker sores. Now, if I could only figure out how to avoid biting the inside of my cheek….

  23. es

    Listerine will also dry up canker sores in one to two days.

  24. JC

    When I took nettle, I was allergic to it and broke out in hives which had to be treated medically.

  25. EP

    I have had canker sores for years. I always have a canker sore going. I have tried almost everything — no results.
    I read your piece on kiwis and have been eating a couple a week for the last two weeks — no canker sores. Going two weeks without a sore is very rare for me. I am cautiously keeping my fingers crossed.

  26. Cynthia Sandford

    Read this article last Sunday. My husband got a canker sore on Thursday and we bought a few kiwis to try this cure. He ate one kiwi in the morning, and by the mid-afternoon the sore was dried up. A second kiwi wasn’t needed. Amazing.

  27. ann broussard

    I was forever getting canker sores and neither my doctor or my dentist could offer any solutions. I had read that sodium laurenth (not sure of spelling) was in toothpaste, and I started looking for a toothpaste that did not contain that ingredient. I started using Biotene toothpaste and I have not had any more canker sores. I was also noticing that my tongue was always sore and that too has gone away. I recommend it to everyone who has canker sores as they are very painful.

  28. Jim

    Before age 18, I had several canker sores in my mouth most of the time, many times a total of 1 sq. in. of them, constant severe pain. Also a few cold sores ea winter. Incidence decreased 60% when Adelle Davis convinced me to take vit C. All incidence stopped dead when I began taking 500 mg/day of L-lysine and learned about arginine/lysine balance (think legume/nut & seed balance). Ceased Lysine several yrs later & ate more beans. Age 64 now and have had none of these oral herpes simplex infections since. (An occasional minor exception when I feast on nuts (think arginine).)

  29. josh

    Canker sores plagued me for years. Check out the first ingredient of almost every toothpaste on the market: sodium laurel sulfate. Now go look at the first ingredient in your hair shampoo: sodium laurel sulfate. Yes, the very same detergent. Using a compound that kills lots of bacteria gives others a chance to gain a foothold that might have been kept in check.
    Bottomline, try using a toothpaste without SLS. Weleda and Jason both make SLS-free toothpaste. It worked miracles for me.

  30. Theodosia

    I would suggest moderation. One kiwi sounds good…how about a whole bunch? Not too good. I peeled a large bowl full, about 4, and ate it while watching tv. My tongue got a prickly sensation and I couldn’t eat them for a long time. I did get over it… eventually. I imagine it was an acid burn of some sort… That’s what I get…

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