About 90 per cent of adults have antibodies to the herpes simplex virus, but only a third of those infected will actually go on to experience cold sores. Cold sore outbreaks vary from person to person and are usually triggered by food allergies, sun exposure, stress, illness and nutritional deficiencies.

Zinc boosts your body’s immune response

In the August 2005 edition of the "Journal of Oral Pathology and Oral Medicine," oral surgeon Felice Femiano, DMD, explains that low levels of zinc cause a decline in the function of T-cells that normally fight cold sores. This can happen, Dr. Femiano says, "within a few days," of decreased blood levels of zinc. In a test tube, Dr. Femiano explains, zinc also counteracts the growth of the herpes simplex virus in the absence of T-cells, suggesting that zinc levels influence the development of cold sore recurrences in more ways than one.

Introduce more Zinc to your diet

Zinc is well-known for its ability to enhance immunity and reduce frequency and severity of herpes outbreaks. Take 50 milligrams of zinc daily and ensure you get plenty of zinc-rich foods such as fish, dairy, egg yolks, pumpkin seeds and legumes into your diet.

Zinc works even in small doses

The 2007 edition of "Integrative Medicine," states that using only 25 mg of zinc taken with 250 mg of vitamin C every day can prevent cold sore outbreaks altogether in some people and reduce the duration of symptoms in others.