Mouth Sore Lysine:

Lysine for Chronic Mouth Sores

by Chet Day and friends

I don't recall my first cold sore or mouth ulcer or canker sore or whatever you call the pesky lip, gum, and/or tongue critters, but I've waltzed with them my entire life, even when I'm eating healthy and living right.

And the same holds true for many health-conscious people, judging from my correspondence since 1993.

Well, today I want to share what I've learned about mouth sores and what you can do to prevent them and/or what you can do to help your body heal them more quickly.

Please keep in mind the operative model I use for health: an identifiable cause exists for every health problem. Once you remove the cause, then your body will heal and return to its optimal state.

If you open your Mosby's medical dictionary to the entry for "herpes simplex," you learn that it is "an infection caused by a herpes simplex virus (HSV), which has an affinity for the skin and nervous system and usually produces small, transient, irritating, and sometimes painful fluid-filled blisters on the skin and mucous membranes."

In other words, modern medicine attributes cold sore outbreaks to the herpes simplex virus.

Mosby's defines "canker sore," as "an ulcerous lesion of the mouth, characteristic of aphthous stomatitis."

Flipping closer to the front of Mosby's, we learn that aphthous stomatitis is "a recurring condition characterized by the eruption of painful ulcers (commonly called canker sores) on the mucous membranes of the mouth. The cause is unknown, but there is evidence to suggest aphthous stomatitis is an immune reaction."

Well, so what?

Yeah, that's my reaction too.

Since 1993, when I started watching for cause and effect in my body, I've observed that I can literally give myself a mouthful of canker sores. All I have to do to CAUSE the pesky outbreak is to...

1) Get involved in stressful situations

2) Eat too many nuts, especially peanuts (usually over several days)

3) Eat too much refined sugar

4) Drink too much straight carrot juice

5) Brush my teeth with a name brand toothpaste

6) Get too much exercise

7) Get too much direct sunlight

8) Work too much instead of sleeping or resting

As a teenager and young man, I would get one canker sore at a time, usually on the underside of my right lip, close to the corner of my mouth.

I still get a canker sore there on occasion, but at age 51 I can also get them on my tongue, my gums, and in various places on the insides of my lips.

Wait, I thought someone who eats and lives healthfully is disease and symptom-free all the time?

That's what a lot of so-called experts and natural health gurus say, but I've not found it to be true, either in my own life or in the lives of those who write to me.

My experience is that many people who eat and live properly still experience cold sores, canker sores, and fever blisters on occasion, and that it's especially true when they violate some of the factors of healthy living.

Okay, let's turn to some solutions.

I do best when I supplement with lysine, an essential amino acid.

If I take a 500 mg. lysine capsule every day along with brushing with Toothsoap, I don't get canker sores.

If I forget or get careless with my supplementation of lysine, and if I also eat poorly, work too hard, or stress out, my canker sores come back like bad chili.

A number of readers have also discovered that lysine solves their mouth sore problems. Let's tune in to what they have to say, shall we?


Hi, Chet, I've suffered from canker sores in my mouth since I was a youngster. I'm 72 now.

About twenty years ago, someone suggested I take L-Lysine to help relieve the problem. I found that somewhere between one and six grams of L-Lysine would stop the pain within a day, and would eliminate the sore within three or four days.

Since the problem reoccurred quite regularly, I talked to my family doctor about taking L- Lysine on a regular basis. He said it couldn't hurt, so I began taking it daily, and the only time I developed canker sores was when I ran out of L Lysine. Several years ago I decided to quit for awhile. I have not had any sores develop.

My wife went along fighting sores for several years by taking L-Lysine when they appeared. Now she takes one gram per day and has no sores at all.

John H.


Chet, I have always used lysine with great success. As soon as I feel a cold sore coming on, I take a bifidophilus supplement and 2500 mg of lysine, three times a day. Works very quickly.

Ken W.


Hi Chet: I have had canker sores since early childhood, and endured all sorts of torture at the hands of those who thought they were helping... powdered alum, cauterizing, etc.

Sometime in the 80's my brother-in-law told me about LYSINE (an amino acid).

Now, when I have an outbreak, I take 1500+ milligrams daily until they heal.

They begin healing within a day or so, and the pain is gone in 3 days.

When I remember to take about 500 milligrams daily, I don't get them at all (or if I do, I up the dosage to 1500 again.).

Also, chocolate, nuts, gelatin, and stress are all triggers for me. It can be good or bad stress. I am so thankful to God for leading me to Lysine, because I constantly had mouth ulcers (3 weeks out of 4) until I learned about Lysine.

Judith H.


Hi Chet,

Have used Lysine for the mouth sores that sometimes follow a viral infection, cold, etc. and it seems to work every time. Of course they heal on their own too:-))

Peace, Love & Harmony, Bev


I was told at a health food store that these are a sign of colon troubles and that I should take L-Lysine and acidophilus.



My husband suffered from cold sores and I now get cold sores as well... a gift from him I think.

It is my understanding that cold sores are caused by a herpes virus, the good news being that the cold sore herpes virus is not supposed to be able to co-exist in the body with the genital herpes virus.

Anyway, when I feel that familiar tingle or whatever it is that precedes a cold sore and leads me to suspect one coming on, I take 500-1000mg of l-lysine up to 3 times a day and knock it out before it can take hold... Other friends use this method successfully as well.

Hope this helps others.

Ruth in sunny Southern California


Chet, I am an avid subscriber to your newsletters, recipes, etc. and wanted to comment on mouth sores.

I myself have suffered from these and have noticed a remarkable decrease by changing toothpastes! Most toothpastes have sodium laureth sulfate which is known to irritate and promote mouth sores.

Also, I have increased my L-lysine, change toothbrushes regularly, especially after an outbreak and try to lower the stress factors.

Hope this helps someone.

Deborah of Naples, FL


Now, those were interesting letters, weren't they?

Here are some food sources for lysine from Marilyn Diamond's cookbook: apples, apricots, grapes, papayas, pears, alfalfa, beets, carrots, celery, cucumber, dandelion, parsley, soybean sprouts, spinach, turnip greens, nutritional yeast, soymilk, and tofu.

With that said, I have to admit I've never been able to get enough lysine from my foods. For me, supplementation works best.

If you decide to try lysine, I recommend capsules rather than tablets because the body will assimilate them better.

Lysine supplementation represents the single best approach I've learned to date for helping to remove the cause of mouth sore problems. From my correspondence over the years, I think many people suffer from a lysine deficiency.

And, as you've seen above, readers suggest taking lysine at the first sign of a mouth sore and then taking several capsules two or three times a day.

Even better, you might want to supplement with lysine on a daily basis. Make it a part of your health program.

That's what I've been doing for several weeks now, and I haven't had a canker sore since making this simple and relatively inexpensive addition to my routine.

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