Brunettes and dark-haired women are not likely to smoke
But they are apt to be dependent on cigarettes. The melanin which gives hair its brown or dark color also slows the liver’s ability to metabolize nicotine. With this, nicotine stays in the system longer, making a dark haired or brunette female to become dependent on cigarettes.
Are women with brown hair prone to non-Hodgkin’s lymphoma (NHL)?
In a study made involving Scandinavian women in 2010, women with brown hair had been cited as the increased risk of NHL compared to the other females with dark, red or blond hair. Interestingly, the results have been claimed no support between the association between the UV radiation and NHL.