A 2013 study published in the British Journal of Cancer, revealed that natural redheads had a reduced risk of developing prostate cancer compared to all other hair colours. The reduced risk was roughly half of that of all other hair colours.

This is a one of a kind study and the results need to be interpreted carefully. The study was conducted on the back of a larger study of Finnish men aged 50-69, all of whom were smokers. The original study was looking at the effect of various supplements on cancer incidence. The results relating to hair colour came from a follow-up questionnaire, which ascertained a number of character traits from the participants. The total number of men involved in the study was almost 21000.