A new University of Colorado at Boulder study indicates that not only do human hands harbor far higher numbers of bacteria species than previously believed, women have a significantly greater diversity of microbes on their palms than men.Incredible the amount of bacterial diversity there is living on our skin. 4,700 different species found and yet only 5 of them were found on everybody.
Using powerful gene sequencing techniques, the team found a typical hand in the new study had roughly 150 different species of bacteria living on it, said Fierer of CU-Boulder's ecology and evolutionary biology department. While the researchers detected and identified more than 4,700 different bacteria species across 102 human hands in the study, only five species were shared among all 51 participants.
The 332,000 gene sequences obtained by the CU team were nearly 100 times greater than those obtained from other studies of skin bacteria also obtained by sampling the entire DNA of microbe communities, known as "metagenomics."
Fierer speculated that skin pH may play a role in the higher bacterial diversity on women's hands, since men generally have more acidic skin, and other research has shown microbes are less diverse in more acidic environments. The findings also could be due to differences in sweat and oil gland production between men and women, the frequency of moisturizer or cosmetics applications, skin thickness or hormone production, he said.
The right and left palms of the same individual shared an average of only 17 percent of the same bacteria types, said Knight. Study volunteers, all CU undergraduates, shared an average of only 13 percent of bacteria species with each other, he said.
Strange that while the title of the article is "women have more diverse hand bacteria than men", no where in the article is the difference ever quantified.
Hmm, maybe with the different pH and bacterias, men and women really do need different deodorants. I thought that Secret's tagline: "strong enough for a man, but pH balanced for a woman" was just a marketing gimmick, but maybe there is something to it. Or then again maybe there is absolutely nothing to it and it is the definition of a marketing gimmick.
via Science Daily