The human gut contains 100 trillion bacteria composed of up to 1,000 different species. Our bacteria are acquired during birth and the first few months of life. The numbers of microbes that grow best in our guts are partly controlled by our genes but also by the food we eat, exercise and other environmental factors.
The diversity of this microbial population has been progressively declining, which is likely to be a major factor in causing the modern epidemics of allergy, auto-immune disease, obesity, and diabetes. Significantly, high rates of antibiotic use, which have an adverse effect on gut bacteria, coincide with increased rates of obesity.
The bacteria in our gut communicate with our immune system via T Regulatory cells and the nervous system via nerve cells in the brain-gut axis. Communication between the brain and gut is vital in controlling the amount we eat, digesting food, and can also influence our mood. The gut microbes are, therefore, vital for optimal gut, and immune and brain functions.
Several studies demonstrate that food high in sugar, low in fibre, chemicals, as well as saturated fats, causes a loss of up to fifty percent of the species of gut bacteria. This is not only associated with an increase in weight but also increases in inflammation and leakiness of the gut wall, which allows bacteria and chemicals to pass into the blood. Low level inflammation affects fat cells which produce more inflammatory signals causing increased insulin release and more storage of fat particularly around the abdomen.
A Mediterranean style diet is very beneficial for gut bacteria. Of particular value are polyphenol compounds found in brightly coloured vegetables and fruit, and in extra virgin olive oil. Polyphenols can also be found in chocolate, green tea and red wine. Polyphenols and fatty acids are broken by bacteria to short-chain fatty acids which promote the activity of good bacteria which can bind lipid particles, clear them from the blood and prevent unwanted bacteria from colonising the gut. Diet is therefore crucial in maintaining a health gut microbiome.
Herbs can also play a crucial part in ensuring diversity of gut bacteria and gut health. Herbs and spices added to food such as turmeric, garlic, ginger, rosemary, and oregano are high in polyphenols. Treatment with herbal medicines can be used to promote healthy bacteria and prevent a leaky gut wall. Of particular value are herbs such as Barberry, Goldenseal and Oregon grape which contain berberine that has been shown to inhibit inflammation promoting bacteria and shift the balance towards beneficial bacteria. Herbs with healing and protective effects on the gut wall, such as meadowsweet, chamomile and marshmallow root can help reduce a leaky gut.
Evidence is mounting that a diverse balanced population of bacteria in the gut is vital for maintaining optimal health and well being. A Medical Herbalist can prescribe herbal medicines and give dietary advice that will allow you to achieve the best population of bacteria for your gut.