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What causes cold sores?


Cold sores are unmistakable. They are those uncomfortable, visible lesions that always seem to surface just before a big date or work presentation. This viral family, linked to the herpes virus, can cause infections throughout the body, but most commonly presents itself around the lips [Source: Habif].

Once the skin (or other tissue) has been exposed to the virus, several factors contribute to the frequency of outbreaks. The nerve must be kept in check by a healthy immune system, a system sacrificed by diets high in refined sugars and sweets. Soft drinks are just one of the popular high-sugar culprits. 

For otherwise healthy individuals, a cold sore episode will clear without treatment. To speed up the process 1-2 days, patients can use tetracaine cream, an over-the-counter medication. Nutritional treatments may include 1,000 mg vitamin C taken up to 3 times a day or amino acids, the building blocks of protein. Many patients clinically report that the supplement L-lysine, an amino acid, is very helpful in treating and preventing outbreaks. Though more research on this supplement is needed, it is tolerated very well at 3,000 mg divided into 2-3 doses a day. Lysine taken at 500-1,000 mg a day can be helpful for prevention. The herpes virus actually uses the amino acid arginine for replication. This nutrient is found in various foods including chocolate, nuts, soybeans, chickpeas and animal proteins. Intake of these foods should be limited for those who experience frequent cold sores.

Canker sores, which occur on the inside of the mouth, can stem from an entirely different issue. Small white lesions on the inner lip or inside of the cheek are called aphthous ulcers. These may be caused by sources other than the herpes virus. Furthermore, they can appear more frequently due to an intolerance to certain foods or ingredients such as gluten, found in grains such as wheat, rye and barley. Other food sensitivities may be triggered by dairy or chocolate. Frequent outbreaks may require keeping a food diary to see if any patterns correlate with the lesions. 

Sodium lauryl sulfate, commonly found in toothpaste, is sometimes linked with sores in the mouth. It is doubtful that it is a problem for everyone, but clinically some patients do better when using toothpaste without this chemical.

Like cold sores, canker sores will typically clear on their own in 1-2 weeks. Those experiencing frequent outbreaks should evaluate possible food triggers and consider adding some fish oils to their diet. Fish oils, particularly in the form of cod liver oil, provide healthy fats to help prevent inflammation of the gum tissue and additional vitamin A (supports tissue in the mouth) and vitamin D (combats inflammation). 

Cold sores and canker sores are often linked to stress. The immune system can become less effective under chronic stress, making you less resistant to illness and more susceptible to infection. Find ways to manage the bustle of the day and keep your immune system on full alert. 


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