AUTHOR: Dr. Jason Bush
There is growing appreciation for the link between the beneficial bacteria inhabiting the gut and good digestive health. But what is really meant by ‘good digestive health’? What characterizes a healthy gut? Is digestive health something you need to worry about or does it only apply to people with specific health concerns?
Being free from digestive issues like irregularity, constipation, or diarrhea is only one aspect of a healthy gut. In fact, good digestive health is central to many important physiological processes, including immune system function, cardiovascular health, and blood sugar control. Perhaps most surprisingly, it is the presence of a diverse group of helpful bacteria inside our gut that are responsible for improving the function of each of these processes.
But how does having healthy bacteria in our gut (or more specifically, in our colon) influence processes that seem so far removed from digestion? The answer to this question is complicated and continues to be informed by ongoing research. Below are some important details to take away from the scientific literature.
Much of our immune system actually sits in close association with the digestive tract where it searches for harmful bacteria and parasites in the food we consume. Remember that food safety is a modern concept and that not too long ago, people were regularly consuming foods that had the potential to make them sick. We now appreciate that having healthy bacteria in our gut helps calm the immune system, preventing inflammation and inappropriate ‘attacks’ on normal foods – a condition commonly known as a food allergy. Chronic low level inflammation is also associated with the development of other serious conditions, such as cardiovascular disease and type 2 diabetes.
However, bacteria in the gut are linked to heart health and blood sugar control even more directly.
As healthy bacteria break down the digestion-resistant carbohydrates in our diet (also known as prebiotics), they produce substances called short chain fatty acids (SCFAs). I’ve described how SCFAs are a great source of energy in another post but they are helpful for other reasons. Certain SCFAs actually inhibit cholesterol synthesis, functioning similarly to cholesterol-lowering medications commonly prescribed to prevent heart disease. SCFAs also instruct a subset of cells lining the colon to release hormones that improve insulin sensitivity, lowering blood sugar levels. While these effects will not replace medication, adding prebiotics to your diet to boost SCFA levels may be beneficial.
Studying the relationship between digestive health and overall health is an evolving field of research – but it is clear that this relationship is an important one. And it should also be clear that maintaining good digestive health means regularly consuming a healthy diet that includes prebiotics to support the beneficial bacteria in your gut. In turn, these bacteria will provide you with a plethora of health benefits.