The Gut-Brain Connection
Have you ever felt like you had butterflies in your stomach before giving a big speech? Or felt nauseous before an important event? These are examples of the gut-brain connection which has become a very popular area of research in recent years.
Although popular now, the idea of the gut-brain connection is not new - in fact over 2000 years ago, Hippocrates, the father of modern medicine, said “all disease begins in the gut.” While this may not be completely true (for ex. some diseases are genetic), there is growing evidence that many chronic diseases do in fact begin in the gut and this has a lot to do with the type of bacteria that live in our digestive tract. Obesity, irritable bowel syndrome, Alzheimer’s disease, anxiety and depression have all been associated with changes in what is known as our gut microbiome.
Our gut microbiome is made up of trillions of microorganisms, mainly bacteria. These bacteria play a role in digesting food and absorbing nutrients as well as metabolism, immune regulation and brain functions and mood. It is believed that 90% of our serotonin, the neurotransmitter that contributes to feelings of well-being and happiness, is produced in our gut.
How does the Gut Microbiome develop?
The type of bacteria we have develops very early in life and many of the factors that influence it are beyond our control. The health and genetics of our parents, if you were born by Caesarean section or vaginally, and if you were breastfed or formula fed all influence our gut bacteria. Additionally, stressful events and illness, antibiotic use, not getting enough sleep, and the type of food we eat all influence our gut health.
What is a healthy gut?
There is still a lot about the gut microbiome that we do not know but in general, it is thought that a diverse range of bacteria is a good thing. We all have good and bad bacteria in us and having enough of the good bacteria can help keep the bad bacteria “in check” to help ward off illness.
What promotes a healthy gut?
Diet has a big influence on our gut bacteria and getting enough fibre is a key factor in helping our bacteria thrive. Only about half of Canadians are getting enough fibre; men and women over the age of 51 years need 30 and 21 grams respectively. Fibre is found only in plant foods so focusing on eating whole grains, fruits and vegetables, and beans and lentils will help you meet your daily fibre needs. Additionally, some foods contain prebiotics which help feed the friendly bacteria. Bananas, onions, garlic, asparagus, oats, barley and apples are a few foods that contain prebiotics.
What about probiotics?
Probiotics are live organisms, such as bacteria, that when consumed, can have a positive effect on us. Some are also found naturally in the colon of our digestive system. Despite popular belief, taking a probiotic supplement isn’t necessary to have a healthy digestive system. There is research that shows that certain probiotics may be helpful in specific circumstances, for example to lessen diarrhea associated with antibiotic use and to improve symptoms of irritable bowel disease.
Some foods also contain probiotics such as Kefir, Kimchi, sauerkraut and yogurt. In Canada, not all yogurt is probiotic so be sure to look for the term “contains live active cultures” on the label. Other foods may also have probiotics added to them. However, foods with added probiotics are not regulated in Canada so there are no standards around how much probiotics there should be in a food. More research is needed to fully understand the health benefits of probiotics and the quantities and types that are most effective.
Aside from a healthy diet, other factors that contribute to a healthy gut include getting enough sleep, managing stress, exercising, quitting smoking, and only taking antibiotics when necessary. We still have a lot to learn about this area of research and how it affects our overall health. One thing we do know though is that consuming a diet of whole foods with plenty of fibre from vegetables, fruits, and whole grains will do our body good.