People with a particular type of gene don't have smelly armpits, yet most of them use deodorants, a new study has found.

Researchers found that even in the group of people that carry gene ABCC11 and don't produce underarm odor, the use of deodorant is prevalent. They added that these people spend on unnecessary purchases and even expose themselves to chemicals that may be harmful. The authors added that people with this gene variation are more likely to have a dry ear wax instead of sticky one.

The study was based on a group of nearly 6,500 women who were enrolled in the Children of the 90s study at the University of Bristol. In this group, about 117 or 2 percent of mothers had a gene variation of the gene ABCC11, a variation that is known to prevent underarm odor. However, these women still used deodorants, which according to researchers, is probably because of cultural reasons.

"An important finding of this study relates to those individuals who, according to their genotype, do not produce under-arm odour. One quarter of these individuals must consciously or subconsciously recognise that they do not produce odour and do not use deodorant, whereas most odour producers do use deodorant. However, three quarters of those who do not produce an odour regularly use deodorants; we believe that these people simply follow socio-cultural norms. This contrasts with the situation in North East Asia, where most people do not need to use deodorant and they don't," said Professor Ian Day, lead author of the study.

Underarm odor occurs when sweat glands produce sweat that then mixes with bacteria. The production of the foul smell depends on whether or not the gene ABCC11 is active. Previous research has shown that this gene is inactive in some people.

"These findings have some potential for using genetics in the choice of personal hygiene products. A simple gene test might strengthen self-awareness and save some unnecessary purchases and chemical exposures for non-odour producers," said Dr Santiago Rodriguez, the first author of the paper.

The study is published in the Journal of Investigative Dermatology.