You wouldn’t think about not brushing your teeth every morning. But when it comes to applying sunscreen, many folks take their cue from the weather, deciding to use it or lose it depending on whether it’s sunny or cloudy.

They should think again. Studies show that applying sunscreen… even on overcast days… could fight off skin cancer.

Australian researchers studied 1,600 adults to see whether using suncreen daily or only occasionally significantly reduced the pre-cancerous lesions known as solar keratoses. One group applied water-resistant sunscreen with a sun protection factor of sixteen every morning to their head, neck, arms and hands. Others simply used sunscreen whenever they wanted.

Those who used sunscreen daily developed 24 percent fewer solar keratoses during a two-year period as opposed to those who only used it occasionally. Younger participants, or those who readily tanned, benefited most from regular sunscreen use.

Left untreated, many keratoses develop into skin cancers known as basal cell or squamous cell carcinoma. In fact, people with solar keratoses are up to 12 times more likely to contract these skin cancers than those whose skin is free of the lesions.

The researchers, who published their findings in the Archives of Dermatology, said people shouldn’t be fooled into thinking cloud cover will protect them from the sun’s ultraviolet rays.

Experts note that you should wait a half-hour for the skin to completely absorb sunscreen before venturing outdoors. Be sure to use a sunscreen with an SPF of 15 or higher.