The power of the gut over health and disease
Did you know that our intestines are home to nearly 2 kilograms of bacteria, tens of trillions of microorganisms, and over 1,000 different species of bacteria with more than three million genes? The intestine has to cope with an unbelievable 30 tons of food in the course of our lives. To manage this incredible workload, the superorgan has developed amazing strategies. It is a huge ecosystem of microbes and bacteria, also known as the gut microbiome. Diverse and constantly evolving, the gut, including the microbiome, is responsible for much more than digestion.
In recent years, more and more studies have shown that the gut plays a central role in overall well-being, a healthy immune system, and even influencing risk for disease and obesity.
5 Facts-to-go briefly & concisely summarized for you!
- The intestine has to cope with an incredible 30 tons of food in the course of our lives
- Our intestines are home to almost 2 kilograms of bacteria, tens of trillions of microorganisms and over 1,000 different species of bacteria with more than three million genes
- The intestinal contents of an embryo in the womb are still completely sterile — not a single bacterium lives in the intestine until birth
- Animal products promote the development of inflammatory bowel diseases by weakening the intestinal barrier
- The composition of our microbiome influences functions such as food intake, energy production, energy consumption and fat storage
The inner world: getting to know the gut
The intestinal contents of an embryo in the womb are still completely sterile — not a single bacterium lives in the intestine until birth. But even during birth in the birth canal, the first bacteria enter the newborn’s body through the mouth — and multiply rapidly there. Which intestinal bacteria these are depends on various factors: Is it a natural birth or a cesarean section? Is the baby breastfed or bottle-fed? Even trivial circumstances like these influence the type of bacteria that colonize the intestine for life.
Gross at first, but having a bunch of bacteria in your gut is actually vital to keeping harmful pathogens and “bad” bacteria at bay. Antibiotics, medications and probiotics, as well as changes in our diet, can disrupt this delicate balance of our microbiome, leading to pathogen overgrowth, increased susceptibility to infection and inflammation throughout the body.
You are what you eat: How diet affects gut balance.
Recent studies suggest that our daily food intake actually has a significant impact on the balance of our gut microbiome and its overall function. In a study conducted at Harvard University, diabetic patients were fed either a plant-based diet (including whole grains, legumes and vegetables) or an animal-based diet (with the addition of meat and cheese) for five days. The study found that the gut microbiome was already responding to such a short-term change in diet. The study also showed that the animal-based diet increased the growth of certain gut bacteria and promoted the development of inflammatory bowel disease.
In a separate study published in the journal Nutrients, researchers conducted an experiment on mice to assess the effect of a particular diet on their gut microbiome. The mice were first fed a low-fat, plant-based diet and then switched to a “Western” diet high in fat and sugar. In their experiments, the researchers noted important changes in the intestinal population, such as the absence of bacteria that protect the intestinal barrier.
An intact intestinal barrier is essential for protection against “invaders” and is thus part of our immune defenses, so to speak. At the same time, the study also showed that a high-fiber vegetarian diet changed the composition of intestinal bacteria and the intestinal environment to such an extent that the growth of “bad” bacteria could be curbed.
Is an imbalance in the gut harmful to health?
A growing body of evidence suggests that an imbalance in the gut microbiome may be partly to blame for the development of certain diseases that have been on the rise over the past two decades — including type 1 and type 2 diabetes, asthma, colorectal cancer, inflammatory bowel disease and even obesity. In an article published in the journal Molecular Aspects of Medicine, scientists examined the link between the gut microbiome, obesity and insulin resistance. They concluded that the composition of our microbiome actually affects functions such as food intake, energy production, energy expenditure and fat storage.
In another study, researchers found a clear link between the gut microbiome and the development of body fat, insulin resistance and subthreshold inflammation, all of which are common features of obesity.
A balancing law
Although the research conducted in this area is promising, many questions remain. However, preventing malabsorption in our gut is key to maintaining an optimally functioning digestive and healthy immune system. This can be easily achieved through a balanced diet rich in fresh vegetables and limited in processed foods. If, at the same time, you still limit animal products and by-products as well as refined sugars, you will promote your intestinal and general health in the long term. This does not mean completely giving up meat from one day to the next. Gradually reducing the consumption of meat and animal products is much easier and more permanent for most people (for example, with “meat-free” days of the week that are slowly increased).
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