The personal grooming routine and expectations of women could be costing them in more ways than one, according to the new research study Mirror, Mirror on the Wall: The Effect of Time Spent Grooming on Earnings.

The study by Elon University in the United States found that for women, an increase in personal grooming time is associated with lower earnings; for example, if a nonminority woman doubles her daily grooming from 45 minutes to 90 minutes, her earnings drop an average of 3.4%.

Men differ significantly by race: Grooming has no effect on nonminority men's earnings, but for minority men, a doubling of daily grooming from 40 minutes to 80 minutes yields a nearly 4% increase in average earnings.

The researchers say grooming signals social identity, and while it has adverse consequences for highly groomed women, it may counter negative stereotypes of minority men.

Click here to access the full study.