Heart Disease 8. 1 Virus Cold sores are caused by a herpes virus, most often the herpes simplex 1 virus. Cold sores should not be confused with canker sores , which are small ulcerations in the mouth. Rather, cold sores are fluid-filled blisters that form on the gums and the outside of the mouth and lips. The blisters, which are contagious, later break, ooze, and crust over before healing.
Recurrences are common and can be triggered by stress, sun exposure, illness, and menstruation.
If the infection is transmitted to the eyes, it can lead to blindness. On the other hand, lysine inhibits viral replication. Therefore, a diet that is low in arginine and high in lysine might help prevent the herpes simplex virus from replicating. A number of studies have shown that increasing lysine intake can reduce the recurrence rate of cold sores. Nonfat yogurt and other nonfat dairy can be a healthful way to increase lysine intake.