Humans are exposed to ultraviolet radiation (UVR), which is mainly of solar origin, and beneficial or harmful effects could result depending on the conditions. All individuals can suffer the harmful consequences of UVR excess, although people with more skin colour have more natural protection and less risk. UVR can produce acute or chronic effects on the skin, lip vermilion, eyes and immune system. The most important is skin or lip cancer; UVR damage can cause blindness. On the lip, UVR can produce acute actinic cheilitis, then evolve into chronic actinic cheilitis/actinic keratosis, the latter increasing the risk of squamous cell carcinoma. Lip cancer is one of the most common cancers of the mouth, usually associated with actinic cheilitis caused by solar radiation. The lip vermilion has natural conditions with lesser protection than the skin, requiring more protective measures. Individuals with fair skin or who spend many hours exposed to UVR for work or recreation require more protection. Thus, oral cancer prevention campaigns should specifically include UVR protection.