Gut microbes can affect your nervous system through the gut-brain axis — the network of nerves, neurons and neurotransmitters that runs through your GI tract. Certain bacteria actually produce or stimulate the production of neurotransmitters (like serotonin) that send chemical signals to your brain.

Gut microbes secrete hormones that regulate aspects of your metabolism, including blood sugar, hunger and satiety.

Just like a garden, your gut microbiome is affected by the nutrients and pollutants it’s exposed to.

Your gut microbiome requires a variety of plant fibers to thrive. Different organisms prefer different whole foods. In turn, they produce short-chain fatty acids and other byproducts that nourish your gut and lower the pH inside, which favors the more beneficial microbes.

On the other hand, a diet high in sugar and saturated fats tends to favor the less helpful types of microorganisms. Processed foods not only lack fiber and micronutrients (vitamins and minerals) but also tend to come with many additives and preservatives, which can be harmful to your microbiome.

Chemicals that may poison your microbiome include environmental toxins like alcohol, tobacco smoke and pollutants. Additionally, pesticides like antibiotics can wipe out the good bacteria along with the bad. Other medications, like acid blockers, can affect your microbiome by changing the pH inside.

The movement of food and waste through your GI tract helps to distribute different microbes into different places along the way. If it’s too fast, they don’t have time to settle or to do their jobs before clearing out. But if it’s too slow, they can overeat and overgrow, spreading beyond their territory.

This show aired Friday August 16th on KDAR 98.3 FM.