WTF Fun Fact 13591 – The Grandmother Hypothesis

Have you heard of the grandmother hypothesis? Basically, it means grandma was right about washing behind your ears!

When it comes to maintaining skin health, certain regions, like behind the ears and between the toes, often get overlooked. Research by the George Washington University reveals why paying attention to these areas is essential. The skin microbiome, which refers to the collection of microbes residing on our skin, has shown variation in composition across different skin regions, be it dry, moist, or oily.

Exploring the Grandmother Hypothesis

The GW Computational Biology Institute set out to explore the widely accepted but scientifically unproven “Grandmother Hypothesis.” Keith Crandall, Director of the Computational Biology Institute, recalls the age-old advice from grandmothers: always scrub behind the ears, between the toes, and inside the belly button. But why? The belief is that these less frequently washed areas might house different bacterial compositions compared to more regularly scrubbed parts of the body.

To put this to the test, Marcos Pérez-Losada and Keith Crandall designed a unique genomics course, involving 129 graduate and undergraduate students. These students collected data by swabbing areas like behind their ears, between their toes, and their navels. For comparison, samples were also taken from drier regions such as calves and forearms.

Revealing Differences in Microbial Diversity

The results were enlightening. Forearms and calves, often cleaned more diligently during baths, displayed a broader and presumably healthier range of microbes. This is compared to hotspots like behind the ears and between the toes. A balanced skin microbiome is essential for skin health. A dominance of harmful microbes can disrupt this balance, potentially leading to skin conditions such as eczema or acne.

The study’s outcomes suggest that cleaning habits indeed impact the microbial population on the skin, further influencing its health. Thus, the age-old advice from our grandparents holds some truth after all!

Implications of the Grandmother Hypothesis

The research carried out by the GW Computational Biology Institute provides significant insights into the skin microbiome of healthy adults. It serves as a benchmark for future studies. There is still a long way to go in understanding the intricacies of how the microbial community on our skin impacts our overall health or disease state.

The study titled “Spatial diversity of the skin bacteriome” marked an essential milestone in the field. It sheds light on the diverse bacterial communities residing in different parts of our skin. Published in the renowned journal Frontiers in Microbiology on September 19, it is a stepping stone to further research in this rapidly evolving domain.

In conclusion, paying heed to the lesser-focused regions of our skin, as our ancestors advised, might be the key to ensuring a balanced and healthy skin microbiome. So next time you shower, remember to scrub those often-neglected areas!

 WTF fun facts

Source: “Skin behind the ears and between the toes can host a collection of unhealthy microbes” — ScienceDaily

WTF Fun Fact 13040 – The Oldest Toothpaste

We tend to think of ancient people as having horrible tooth decay. In fact, it’s often referred to went talking about their shorter lifespans. But it turns out that toothpaste (and teeth cleaning generally) is an ancient concept. The oldest toothpaste comes from Egypt.

Ancient toothpaste

Dental hygiene has always been of relative importance. People who lived thousands of years ago may not have had twice-yearly dental cleanings, but they did have bristled toothbrushes and toothpaste.

According to Open Culture (cited below): “not only did ancient people use toothbrushes, but it is believed that ‘Egyptians… started using a paste to clean their teeth around 5000 BC,’ even before toothbrushes were invented.”

The world’s oldest toothpaste recipe

According to The Telegraph, in 2003, the oldest toothpaste formula (so far) was found at a Viennese museum. It dates from the 4th century AD. The Egyptian papyrus (which is written in Greek) “describes a ‘powder for white and perfect teeth’ that, when mixed with saliva, makes a ‘clean tooth paste.'”

It requires:
1 drachma of rock salt (about one-hundredth of an ounce)
2 drachmas of mint
1 drachma of dried iris flower
20 grains of pepper

The ingredients are to be crushed and mixed together.

Dental hygiene surprises

Rock salt, mint, and pepper are probably not a recipe for the most pleasant experience for your gums, but it would be refreshing.

Once we get into the middle ages, we start to see things like charms and amulets used for dental health – so at least ancient Egyptian toothpaste would remove some germs.

Dental health care is also described in Gilbertus Anglicus’ 13th-century Compendium of Medicine. It advises rubbing teeth with a cloth to remove “corrupt matter.”

It’s pretty clear that people have long understood the importance of dental hygiene for health.  WTF fun facts

Source: “Try the Oldest Known Recipe For Toothpaste: From Ancient Egypt, Circa the 4th Century BC” — Open Culture