Just in case you’ve managed to overcome feeling creepy about the bacteria-laden shopping carts, a recent report suggests that people actually have even more bacteria on their hands than scientists previously thought. And according to this study, even though women wash their hands more often than men wash their hands, women’s hands test for the widest variety of different types of bacteria, as well as the largest number of bacteria.
More of our stone walls
The study was done with students after they had taken a written exam… on samples taken by swabbing the students’ palms. All the students showed Streptococcus, Staphylococcus, and Lactobacillus, but surprisingly, forty-five percent of the bacteria found on their hands were from rare species of bacteria. Each student had an astonishing average of 150 species and 3,200 bacteria on their hands. Each hand, even in the same person, had its own individual mix of bacteria, and certain bacteria were more common on the dominant hand in a right handed or left handed person.
No conclusions were reached as to why women’s hands harbor more bacteria and more diverse bacteria than men’s hands do. One theory is that because men’s skin is more acidic than women’s skin, it provides a less favorable growing environment for bacteria. Other possibilities… cosmetics, skin thickness, hormones, and variations in oil and sweat production.
This study also made the unexpected discovery that every person has a unique “bacterial fingerprint.” It suggests that it may someday be possible to tell who has touched what by identifying the bacteria left on the object, in much the same way that fingerprint identification is used today.
A final point from this research is that although washing hands does cut down on the number of bacteria, the diversity of bacteria recovers very quickly. Some bacteria actually preferred growing on clean hands… but washed or unwashed, women’s hands always had the most bacteria.
Somehow that just doesn’t seem fair!!!