An ancient medicinal clay whose use stretches back at least 2,500 years has yielded insights that could help improve gut health in the modern age, a study says.

The clay in question – known as Lemnian Earth (LE) – has long been “highly valued” as a therapeutic. Clay found on the Greek island of Lemnos was shaped into small pellets or tablets and taken orally, either alone, as a powder, drunk with wine, or mixed with herbal substances.

There are documented records of almost continuous medicinal use of clay for over two millennia. Medical literature from the fifth century BC to the late 19th century reveals that it was prescribed to treat a number of ailments over time.

For example, it was used as an “antidote” to poisons or poisons, as a preventative against the plague, and as a treatment for intestinal problems.

Despite a long tradition of use, a comprehensive understanding of what makes LE, a seemingly ordinary clay, therapeutic has eluded researchers. (The actual effectiveness of clay can vary greatly depending on the condition involved and remains unclear.)

Over the past few years, a team of researchers has been evaluating the existing evidence associated with LE. This led them to hypothesize that its potential medicinal properties were not necessarily inherent to the clay, but could instead be the result of an interaction between the material and certain fungi.

These fungi may have been added to the clay accidentally and then intentionally in different ways at different times, according to the scientists.

In the latest study published in the online journal PLOS One, the team set out to test this hypothesis. To do this, the authors grew their own fungus in the laboratory, combined with two different clays.

The selected clays had mineralogical compositions similar to those found in historical LE samples. The chosen mushroom was Penicillium purpurogenuma member of genera (groups of species) identified in historical samples.

These experiments led to the creation of certain bioactive compounds, which were then fed to mice to determine their effect on the microbiome – the collection of microorganisms – in the rodent’s gut. In this case, mice were used as a model animal to study biological processes that may be relevant to humans.

The results indicated that the combination of certain clays with certain beneficial fungi produced compounds that had antibacterial properties as well as a positive effect on the gut microbiome of the mice. In humans, a healthy microbiome is strongly linked to good gut health, not to mention overall health, and affects immunity, metabolism, and even mental well-being.

The findings of the latest study support the argument that the therapeutic properties of LE may have been based on the potential to regulate the gut microbiome. The study could pave the way for future research aimed at promoting gut health in humans, according to the researchers.

“Our reconfigured 21st century Lemnian Earth shows that this ancient medicine has the potential to promote good gut health in people living today,” study author Simon Milling, professor of immunology at the University of Glasgow, said in a press release.

Link

Milling, S., Ijaz, UZ, Venieri, D., Christidis, GE, Rattray, NJW, Gounaki, I., Andrusaite, A., Hareendran, A., Knapp, CW, Jones, AX, & Photos-Jones, E. (2024). Beneficial modulation of the gut microbiome by Penicillium purpurogenum leachate in the presence of clays: A model for the preparation and efficacy of historical Lemnian Earth. PLoS One, 19(12), e0313090. https://doi.org/10.1371/journal.pone.0313090