Fever blisters, also known as cold sores, generally affect the skin outside your mouth -- lips, chin and cheeks -- although they may also occur on the roof of your mouth or on your gums. Your physician may recommend medications to help heal these sores or to prevent outbreaks, which are caused by the herpes virus, but there are foods you should avoid as well.

Salty Foods

When a fever blister attack occurs, avoid consuming foods high in salt. Salty foods, such as pretzels or soy sauce, may aggravate irritated sores. Additionally, too much sodium in your diet -- a component of salt -- can throw off the balance of moisture in your body; correct moisture levels play an important role in the healing of fever blisters and other wounds. Keep your sodium levels to 1,500 milligrams or less each day. Some home remedies call for finely ground salt to be directly applied to fever blisters as a way of drying wounds, but no scientific evidence suggests this is effective for healing.

Spicy Foods

Some people find that eating spicy foods triggers an outbreak of fever blisters; other people find that spicy foods irritate the skin and cause additional pain in the cold sore area rather than cause the outbreak in the first place. Whatever the case is for you, it is a smart idea to avoid consuming spicy foods. This can apply to foods that are hot to the taste, such as hot wings, jalapeno peppers or hot pepper sauce, or only pungent, such as curries or foods that contain a large quantity of paprika.

Foods Containing Arginine

Arginine, an amino acid, triggers outbreaks of fever blisters, particularly when you have a low quantity of lysine, another amino acid, in your meal plan. Avoid foods such as chocolate, soy beans, garbanzo beans and cereals, which are rich in arginine. Protein-rich foods such as poultry, nuts, seafood, pork and beef also contain high quantities of this amino acid.

Foods With Rough Textures

An important key to fever blister healing is to keep the sores clean and dry while allowing them to heal 1. Eating foods with rough textures may disturb the blisters and irritate them, postponing the process of wound healing. Do not consume potato chips, crunchy cereal, hard pretzels and crusty breads as they all have abrasive textures that can pop blisters and scratch healing sores.