I am very susceptible to canker sores. I know they aren’t solely caused by [nutrition issues], but can I do anything from a nutritional standpoint to reduce their frequency?
I have read that I should supplement lysine. How much do I need, though?
— Roxana (Last name withheld)
Canker sores are indeed tricky because they can be spurred by a variety of factors. Sodium lauryl sulfate (the compound in most toothpastes responsible for foaming), for instance, can trigger canker sores in individuals who are prone to them.
From a nutritional standpoint, supplementing lysine is only half the tale.
Alas, let’s start at the beginning.
Lysine is an essential amino acid found in high amounts in red meat, poultry, eggs, soybeans, cheese, and nuts. Remember, “essential” means our bodies are unable to produce it, so we must get it from food. Lysine is the only essential amino acid found in very low amounts in grains.
The bulk of research on canker sores and amino acids goes beyond simply getting sufficient lysine, though. The key is to simultaneously restrict one’s intake of another amino acid, though one that is not essential — arginine.
Alas, peanuts, tree nuts and chocolate have very high arginine to lysine ratios. While not everyone responds to this diet, many people are able to keep tabs on canker sores (both by reducing the number of outbreaks and by cutting short their duration) by drastically limiting their intake of nuts.