Washing hands
Scientists have said excessive hand washing should be avoided to allow for body to take in good bacteria.Getty Images

Scientists have revealed that excessive hand washing should be avoided to allow the body to take in friendly bacteria that has over time diminished from the immune systems. The suggestion comes from Dr. Justin Sonnenburg, associate professor of microbiology and immunology at Stanford University School of Medicine who recommended gardeners and dog walkers to skip washing hands once in a while.

"The extremely low-fibre intake in industrialised countries has occurred relatively recently," said Dr. Sonnenburg. "Is it possible that over the next few generations we'll lose even more species in our gut? And what will the ramifications be for our health?

"We would have difficulty living without them. They fend off pathogens, train our immune systems and even guide the development of our tissues. Simple tweaks in our cultural practices, for example, not washing our hands after gardening or petting our dogs could be a step in the right direction."

Due to the disappearance of healthy microbes from the human gut over time, it is essential that certain practices be changed to ensure humans are less prone to allergies that come with a weakened immune system. Increasing the intake of fibre can also bring in added benefits since bacteria are known to live on fibre.

According to scientists, these changes are necessary since once the bateria disappears from the body, they will not return even if there is a switch to a healthy diet. The bacterial deficiencies will also not be reversed by increasing fibre intake once the bacteria are gone, as determined by research experiments carried out on mice at Stanford, reported The Telegraph.

"Numerous factors including widespread antibiotic use, more-frequent caesarean sections and less-frequent breastfeeding have been proposed for why we see this depletion in industrialised populations," said the research study's lead author Dr. Erica Sonnenburg, a senior research scientist at Stanford.

"We asked ourselves whether the huge difference in dietary fibre intake between traditional and modern populations could, alone, account for it ... There are very few ecosystems where low species diversity is a good thing. There's no reason to think our gut is any exception."