Eating these microbes can prevent several diseases – 2024-05-06 09:06:37

In gardening families, it has been found that soil microbes are transported to the intestines of the entire family, even though there was only one gardening enthusiast in the family. Colourbox

Eating safe microbes from the soil can promote the development of intestinal microbiota and immune defenses and have a healing effect on our mental health, according to a review by the Natural Resources Center and the University of Tampere.

During its evolution, humans have been exposed to soil microbes, which is central to the development of intestinal microbiota and immune defense. An adult’s gut can contain 1.5 kg of gut microbes and several hundreds or thousands of different species. The majority of microbes are bacteria, the compounds produced by them regulate, among other things, metabolism, hormone function and inflammatory factors.

The diversity of soil microbes is missing from many people’s plates and intestines these days. According to a review published in the journal People and Nature, this may be one important reason behind many of today’s health problems.

The diversity of intestinal microbes has decreased due to urbanization, western diet and global nature loss. At the same time, the prevalence of chronic, non-communicable inflammatory diseases has increased in urbanized societies. An imbalance of the intestinal microbiome has been linked to obesity, cardiovascular diseases, diabetes, inflammatory bowel diseases, central nervous system diseases and allergies, among other things.

– The microbial community in our intestines may be compatible with our urbanized environment, but at odds with our human biology, Norwegian Natural Resources Institute PhD researcher Marja Roslund says in the announcement.

Pros and cons

Research doctor Roslund, docents Aki Sinkkonen and Olli Laitinen analyzed the scientific evidence for the benefits and harms of eating soil microbes in an extensive literature review.

According to the review, human experiments have proven that exposure to soil microbes modifies the human microbiome, which can have a positive effect on the immune system. For example, in gardening families, it has been found that soil microbes are transported to the intestines of the entire family, even though there was only one gardening enthusiast in the family. Animal experiments have shown that exposure to soil microbes can balance intestinal function, prevent allergies and autoimmune diseases, and reduce anxiety and stress.

The review also mapped the current research gaps and challenges that have prevented research and utilization of the effects of eating soil microbes for health promotion purposes.

– In the literature search, no research was found in which people were fed safe and researched soil microbiota for the purpose of promoting health. Research has focused more on the risks of eating soil than the benefits, which shows a critical research gap, Roslund commented.

A planetary diet promotes the health of the planet and people, and consists largely of vegetables, fruits, whole grains, legumes, and oils containing unsaturated fat, and may also include moderate amounts of fish and chicken but only a little red meat. However, the diversity of soil microbes is missing from nutritional recommendations and also from the planetary plate model.

In many cultures, people have eaten soil either by accident or on purpose to remove harmful substances from the body and due to a lack of nutrients. The phenomenon is still common among some indigenous peoples, especially during pregnancy. Soil microbes can also be eaten unconsciously.

– We eat soil microbes because they are inevitably carried along with the plants grown in the soil. Or at least we eat if our diet includes a variety of organic vegetables that have been grown in clean and rich microbial soil, says Sinkkonen.

However, eating soil directly from the ground is not safe because many pathogens and harmful substances can be present in the soil. Heavy metals, oil hydrocarbons, microplastics and drug residues can be found in the soil. In addition, there may be antibiotic-resistant bacterial strains and pathogens such as parasitic worms in the soil.

While probiotics have been found to promote gut balance and health, they often only contain one or two tested strains of bacteria. Microbial diversity has not been taken into account, even though research shows that this has beneficial health effects.

– We need new technologies and especially research and development work, so that the beneficial health effects of soil microbes can be harnessed for society’s use while avoiding the risks associated with eating soil. This development work can have far-reaching public health and economic benefits, Laitinen states in the press release.

The research was financed by Valio Oy. The literature review was carried out in cooperation with the Natural Resources Center and the University of Tampere in the Environmental and Social Connections of Elonkirjo’s Impoverishment (BIOD) program funded by the Strategic Research Council (STN), in the Well-being with Biodiversity Intervention (BIWE) project.