Fever blisters are itchy and painful. They usually develop on the borders of the lips, or less often, inside the mouth or elsewhere on the face. All fever blisters are caused by infection with one of two types of the herpes simplex virus. However, not all people with the virus get fever blisters. For many people, fever blisters only follow specific triggers like stress, sickness, fatigue or eating foods that contain a high ratio of one amino acid called arginine to another one called lysine.
Nuts and Seeds
Nuts and seeds contain the highest ratios of arginine to lysine. Macadamia nuts represent the biggest culprits, topping out among all nuts and seeds with an arginine to lysine ratio of 78 to 1. By contrast, pistachio nuts offer the lowest ratio at 1.8 to 1. The ratios of other popular nuts in descending order include: walnuts, 5.4 to 1; hazelnuts, 5.3 to 1; pine nuts, 4.5 to 1; brazil nuts, 4.4 to 1; almonds, 4.2 to 1; pecans, 4.1 to 1; peanuts, 3.3 to 1; and cashews, 2.3 to 1. The ratios of other popular seeds, also in descending order, include sesame seeds, 4.6 to 1; pumpkin seeds, 4.3 to 1; and sunflower seeds, 2.6 to 1. By comparison, foods recommended for people with fever blisters--like lean cuts of chicken or fish and low-fat dairy products---often feature arginine to lysine ratios between 0.35 and 0.75 to 1.
Gelatin
Gelatin is another fever blister-food culprit. Although gelatin is missing many amino acids required by the human body, it's rich in arginine, with a ratio of nearly 2 to 1 over lysine. Although gelatin desserts present an obvious source of gelatin, gelatin is used as a stabilizer many other foods. Surprising examples include candies like gummy bears, thickened soups like consomme, sweet or savory molded foods like terrines and pates, and some frozen treats. For people who prefer not to read labels, foods labeled "vegan" are suitable choices since gelatin is derived from the animal protein collagen and thus will not be present in vegan foods.
Chocolate and Cocoa
For many people with fever blisters, chocolate and cocoa are the most difficult foods to give up. Sweet, semi-sweet and unsweetened chocolate and cocoa all feature arginine to lysine ratios of about 1.13 to 1. The good news is that foods like chocolate pudding, chocolate ice cream, chocolate milk, chocolate cake and others that use small amounts of chocolate or cocoa to flavor other foods mostly follow the arginine to lysine ratios of their main ingredients. For example, chocolate milk has a ratio of 0.46 and chocolate pudding has a ratio of 0.5---close to the 0.45 ratio of milk. Chocolate cake, chocolate chip cookies without nuts and chocolate-coated granola bars are nearly even matched in the ratio of arginine to lysine--between 0.9 and 0.95 to 1. White chocolate or artificial white chocolate, also known as confectioner's coating, is also safe. Since it's flavored with milk proteins instead of cocoa, it follows the 0.45 to 1 ratio of milk.
References
- American Social Health Association: Learn About Herpes
- "Integrative Medicine"; David Rakel, M.D.; 2007
- United States Department of Agriculture: National Nutrient Database for Standard Reference
