Is coffee the new sunblock?

Good news: your daily brew doesn't make you dehydrated, a new US study finds. (Photo: ©discpicture/shutterstock.com)

Drinking coffee can lower your risk for malignant melanoma, according to a new study from the Division of Cancer Epidemiology and Genetics at the National Cancer Institute in the U.S.

Spring-boarding on evidence that suggests coffee could protect against non-melanoma skin cancers, the researchers set out to learn whether it has this effect against melanoma.

They worked with a database of 447,357 non-Hispanic white subjects who in 1995 and 1996 responded to a questionnaire about their diet and provided follow-up information 10 years later, on average.

At the start, all subjects were cancer-free and the research team determined their frequency of exposure to ultraviolet (UV) rays based on where they lived and adjusted the data accordingly.

Subjects were also assessed for body mass index (BMI), age, sex, alcohol intake, smoking history and the amount of exercise they got and the study data was, again, adjusted.

High coffee consumption -- at least four cups per day of caffeinated coffee, not decaf -- was associated with a 20 per cent reduction in risk of malignant melanoma.

The more coffee subjects drank -- starting at one cup a day until four or more -- the less at risk they appeared to be for malignant melanoma.

It should be noted that the protective effect was observed only against malignant melanoma and not against melanoma in-situ and the researchers say their results are preliminary and may not apply to all populations.

The study, which researchers say merits further research, was published in the Journal of the National Cancer Institute.