Persons with a low bacterial diversity in the intestine are often obese and bear an increased risk for the development of obesity-associated concomitant diseases, according to French study. A further study showed that a low bacterial diversity in the stool is associated with intestinal cancer. The bacterial colonization of our intestines should therefore be as diverse as possible!
When we hear the word “bacteria”, many people first think of pathogens and how they can best protect themselves against them. But certain bacteria offer the best protection and fulfill important functions in the body, and this is only now becoming common knowledge. Intestinal flora plays an essential role for our health and well-being, but what exactly does it do?
We all carry between 10 and 100 trillion bacteria in us.
Intact Immune System and Functioning Digestion
Regarding the bacterial colonization of our intestines, we can see an ecosystem, because there are many hundreds of species of bacteria. Healthy middle-aged adults carry 10 to 100 trillion – mainly anaerobic – bacteria. On the one hand, they represent a protective barrier to the outside world and keep pollutants and germs away.
On the other hand, the intestinal flora is not only critical for an intact immune system, but also helps the body to digest and convert the food components into active forms.
Damage caused, for example, by the intake of broad-spectrum antibiotics prevents our intestinal flora from performing these important tasks. These not only kill dangerous pathogens, but also our “good” intestinal bacteria. Although taking antibiotics can be unavoidable or even life-saving in many cases, our intestinal flora can be well protected by taking probiotics. You can find out more about this topic here.
Diversity Matters
It is important that the existing types of bacteria are as diverse as possible. They communicate with the entire organism by exchanging signals via the blood, nervous and immune systems and thus exert influence on the entire body.
We can even be influenced in our behavior, for example, by having a craving for sweets due to an incorrect colonization – a so-called dysbiosis – of the intestine with candida (yeast fungi).
Energy-rich meals, environmental factors, and increasing life expectancy increase the occurrence of metabolic diseases.
The Occurrences of of Metabolic Disease are Rising Worldwide
It is no coincidence that the French scientist Emmanuelle Le Chatelier from the National Agronomic Research Institute, together with research teams from several countries, investigated the relationship between intestinal microbiata and obesity, one of the global epidemics of our time.
Many researchers have warned of a metabolic health crisis caused by modern unhealthy lifestyles: abundant, readily available energy-rich meals, unhealthy environmental factors, and increased life expectancy all contribute to an increase in metabolic diseases worldwide.
Twin and family studies have found that there is a certain hereditary component, since some people are more susceptible than others to an environment that promotes obesity. However, the microbiata – the genome of microorganisms that colonize our body – appears to play an even greater role, as Le Chatelier’s research confirms.
Low bacterial diversity: obesity and increased risk of concomitant diseases such as diabetes.
The researchers examined the microbial composition of the intestines of 123 normal-weight and 169 obese Danes. The participants differed in the number of intestinal microbe genes and therefore in the bacterial diversity of their intestinal flora.
It was found that individuals with a lower bacterial diversity (23% of the population) were significantly more obese and also increased more than those with a more diverse intestinal flora. Based on the variation in the intestinal microbiata, it was also possible to filter out persons who had an increased risk of progression of obesity-associated concomitant diseases.
Participants with fewer bacterial species were more often insulin resistant, had dyslipidaemia (fat metabolism disorder) and were more prone to inflammatory diseases compared to people with a high bacterial diversity.
It was also found that only a few bacterial species were sufficient to distinguish between subjects with high and low bacterial diversity and between thin and obese participants.
Less Bacterial Diversity and Potentially Harmful Microbes in Rectal Cancer Patients
Scientists from the New York University School of Medicine discovered a similar relationship between microbial diversity and the incidence of rectal cancer. They investigated whether an altered colon microbe community is associated with the risk of rectal cancer.
The researchers discovered that rectal cancer is associated with reduced bacterial diversity in stool and that tumor patients had more potentially harmful microbes in their stool samples than healthy volunteers. Since intestinal bacteria are potentially modifiable, the researchers hope that findings from these or similar studies could one day contribute to the prevention of intestinal cancer.
Early Imprinting Crucial
For the first time, the individual composition of the intestinal flora is influenced by contact with the mother – the bacterial colonization of the mother already influences the child at and after birth. Today, we know that it is also beneficial for children to spend time on a farm with stables and mixed animal husbandry at an early age. These children are less prone to allergies and asthma.
