Oral nicotinamide and actinic keratosis: a supplement success story.

Nicotinamide has shown potential as a safe and effective intervention for the prevention of malignant and premalignant skin lesions. Recent studies have shown that nicotinamide, in both oral and topical forms, is able to prevent ultraviolet-induced immunosuppression in humans [1,2,3] and mice [4,5]. Immunosuppression is a known factor for the progression of premalignant lesions, such as actinic keratosis [6]. Murine studies have shown that nicotinamide is also able to protect against photocarcinogenesis [4,5]. Preliminary human studies suggest that nicotinamide may help prevent skin cancers and enhance the regression of actinic keratoses.