The bacteria within: friend or foe

Have you ever experienced that ‘gut feeling’ when meeting someone for the first time? Or perhaps you’ve felt ‘butterflies’ in your stomach when nervous? Do stressful situations make you feel hungry? 

You’re not imagining things. It turns out that our brain and gut are in constant communication via an extensive network of neurons, chemicals and hormones that can have a direct influence on our mental and physical state. An unhealthy gut biome (dysbiosis) can send signals to the brain, just as a troubled brain can send signals to the gut. Scientists refer to this two-way signalling as the gut-brain axis. It’s very real and it’s revolutionising our understanding of health and wellbeing.

Our gut is populated by trillions of microscopic organisms. These include over a thousand species of bacteria that play a key role in food digestion, absorption of nutrients and synthesizing vitamins. These microbes also influence metabolism, body weight, immune function, brain functions and even mood. In fact, some bacteria are directly involved in the production of neurotransmitters such as serotonin and dopamine. There are many factors that dictate the type and the number of bacteria found in the gut. 

Did you know that your gut microbiome is unique to you, beginning at birth? Thereafter, new microbes are continuously added through our environment. The presence of these microbes are a direct result of genetics, the type of microbes encountered during childbirth, stressful events, illnesses, etc., 

Beyond the gut microbes that we inherit, our lifestyle – particularly our diet – influences what type and number of helpful or harmful bacteria will populate our gut. 

So, how do we build a diverse population of good gut bacteria? Research shows that within days of eating a fibre-rich diet, we can begin to change our gut flora. It seems that the good bacteria love leafy greens, whole grains, fresh fruit, legumes and fermented foods.

By contrast, the consumption of highly processed foods, high in sugar and saturated fats can promote the production of unhealthy gut bacteria that have been associated with a host of diseases such as Alzheimer’s, cardiovascular disease and diabetes, just to name a few. 

There is still much to learn about the gut-brain axis, but scientists are hopeful that understanding the complex ecosystem that lives within us may hold the key to tackling everything from obesity to depression.  

Sherry Fader is a certified Nutrition Educator, NE, Bauman College, Penngrove, California. 


Share this edition