British news network BBC reported on Nov. 4, "Women have a greater range of different types of bacteria on the palms of their hands than men," citing research by the University of Colorado. According to the report, more than 4,700 kinds of bacteria species were found on the hands of 102 people studied, and women had an average of 50 percent more species on their hands than men.

Prof. Noah Fierer of the University of Colorado said it is more difficult for bacteria to live on men’s hands, as they tend to have more acidic skin than women. Other factors, such as differences in sweat, oil glands or hormone production, and the fact that women tend to use more cosmetics, like moisturizers, to increase moisture level, might have contributed to the result.

The study also revealed that washing hands with water does not help reduce bacteria, showing that there are certain types of bacteria whose number increases after washing. The research team advised that using anti-bacterial soap when washing hands is an effective way to reduce the risk of disease.