Scared of germs? Think cleanliness is a virtue? Coating your kids with anti-bacterial gel? You might reconsider those ideas when you learn that self-induced (or medically prescribed) bacterial genocide may be doing more harm than good. Of course, let me be clear that the discovery and wise use of antibiotics remains one of the most important advances in science and medicine in the last 100 years; and of course antibiotics can clearly save lives. That said however, new thinking and research demonstrates the incredible importance of our 100 trillion shadow residents – our bacteria – collectively known as the microbiome.
Our human cells and DNA are outnumbered 10 to 1 by bacteria in and on our body, and that does not even include the viruses and fungi we carry inside and out! These bacteria, especially our gut bacteria, play critical roles in health and disease from before birth well into adulthood. Not only do they form a physical barrier against the outside world, our bacteria also make important proteins that can alter the cascade of immunity from resilient to frail and even from skinny to fat.
An example of research in the gut microbiome shows that a greater diversity of bacterial species in our gut is associated with better health. Specifically, individuals with diabetes and obesity (now known as diabesity) have significantly fewer species of gut microbiota compared with lean non-diabetic adults. More bacterial diversity equals better health. Even more fascinating, scientists have studied the microbiome of identical twins, where one is lean and one is obese. If you transfer the gut bacteria from the obese twin to the healthy lean mouse, the latter will become obese. However, if you make the newly obese mice live with the skinny mice, the bacteria from the skinny mice will find their way into the obese mice and reverse the obesity! Interestingly, it does not work the other way around.
So the concept of the microbiome, or as I like to call it the bacterial zoo in my belly, is critical to being healthy and staying healthy. We are deeply connected to not only our own microbiome, but to the microbiome of our family, our community (I wonder, is there an ex-pat microbiome, I bet it is very resilient!), and even our pets. Yes, pets may make us healthy by increasing the breadth of bacteria in our bodies.
In another example, doctors have shown that when women are pregnant, the bacterial ecology of womb radically increases the presence of rare bacterial species while decreasing the presence of typically common bacteria. Why? The fact is, it is important that before birth, babies are given a huge repertoire of bacteria that are necessary for immunity and to colonise the gut for proper digestion.
And of course a simple Google search for “microbiome” will show that more and more studies suggest that children who receive frequent antibiotics are at higher risk for immune-related disease such as asthma, irritable bowel disease, and no doubt, food allergies.
So when you think about your own microbiome, think resilience. The more bacterial diversity you maintain, the more good work your gut can do, the more specialized your body is. Antibiotic usage, whether by prescription or by accident (e.g., certain processed foods, skin care products) reduces your resilience and makes the (surviving) bacteria even more hearty.
I regularly see adults and teens with what I call the “broken gut syndrome”. Typically these people have been wildly over-treated with antibiotics, anti-parasitics, and anti-fungals, rendering their guts “nude”, ineffective, and hypersensitive. Overuse of antibiotics goes beyond the simple yet important worries about developing resistance. Overuse clearly leads to serious and potentially permanent changes in your microbiome. Probiotics are a reasonable idea but likely oversimplify the issue. Simply put, you should maintain and encourage as much bacterial diversity as possible. A diet of fresh vegetables and plant-based foods can increase your bacterial diversity quickly.
A final thought: I am of the age that I remember the TV ads comparing your brain on drugs to frying an egg. Now consider the same idea: This is your healthy microbiome and this is your microbiome on fast food. Eating healthy and being smart about antibiotics throughout life will help keep you away from many medical problems.