New research has found a link between gut bacteria and anxiety — the diversity and quantity of your gut bacteria can affect your anxiety levels. Scientists believe this could play a role in treating PTSD, or post-traumatic stress syndrome.

In the study, researchers subjected mice to stressful conditions until they showed signs of anxiety and stress: shaking, diminished appetite, and reduced social interaction. Fecal samples showed the stressed mice had less diversity of gut bacteria than calmer mice who had not been subjected to stress.

When they fed the stressed mice the same live bacteria found in the guts of the calm mice, the stressed mice immediately began to calm down. Their stress levels continued to drop in the following weeks.

Brain scans also showed the improved gut flora produced changes in brain chemistry that promotes relaxation.

These biomarkers, according to researchers, can indicate whether someone is suffering from PTSD or is at a higher risk of developing it. Improving gut microflora diversity may play a role in treatment and prevention.

The role of healthy gut bacteria in the military

Because about 20 percent of Iraq and Afghanistan war veterans suffer from PTSD, the military is interested in the potential of influencing gut bacteria to manage and predict the risk of PTSD, anxiety, and depression. Enhancing gut microflora may also help submarine crews who go for long periods in confined spaces and with no daylight.

How to improve the health of your gut bacteria for anxiety, PTSD, depression, obesity, eating disorders

The quality and diversity of gut bacteria, or the “gut microbiome,” has been linked to not only anxiety, but also depression, obesity, eating disorders, autism, irritable bowel syndrome, and many other common disorders.

In other words, if you want to improve your health, you need to tend to your inner garden and make it richly diverse and bountiful. Although we’re still a ways off from a magic-bullet approach, there are many ways you can enrich the environment of your gut microbiome:

Cut out foods that kill good bacteria and promote harmful bacteria: Sugars, processed foods, processed carbohydrates, alcohol and energy drinks, fast foods, food additives, and other unhealthy staples of the standard American diet.

Eat tons of fiber-rich plants, which good bacteria love: All vegetables but especially artichokes, peas, broccoli, Brussels sprouts, as well as fruits. Either way, eat a large diversity of veggies on a regular basis instead of the same thing every day.

Use probiotics: Live, “friendly” bacteria that bolster your gut’s population of healthy microbes. Read the label to make sure they are high in live bacteria. Dietary fiber nourish these friendly probiotic bacteria. This combination of pre- and probiotic support is vital for healthy gut bacteria.

Eat fermented foods: Sauerkraut, kimchee, kombucha, and yogurt contain live microbes, and can also help boost the probiotic content of your digestive tract. Not all fermented foods have live cultures so make sure to read the labels.

Protect your existing gut flora: Medications, age, health status, and stress influence your gut microbiome. Eating a fiber-strong, gut-friendly diet and supplementing with probiotics and fermented foods is one of your best strategies for supporting gut health, a healthy mood, and stress resiliency.

We live in a time of unprecedented abundance of food and medical advances yet we are sicker than ever. It is considered normal to suffer from insomnia, PMS, depression, chronic pain, heartburn, constipation, diarrhea, and so on. But in reality these are our bodies’ warning signs that something is wrong.

“All disease begins in the gut,” said Hippocrates. Understanding digestion helps you understand why you stay well or get sick.

From north to south

Digestion starts in the brain. When your brain gets the message you’re about to eat, it turns on the parasympathetic “rest and digest” part of the nervous system to prepare the organs for their jobs. When we eat while distracted, busy, or anxious our saliva won’t be as rich in digestive enzymes, our stomach won’t be sufficiently acidic, and our pancreas will not secrete enough digestive juices.

Age-old rituals around meal times serve a benefit by giving our bodies the chance to ease into the rest-and-digest state.

The mouth and the stomach

The majority of our digestion takes place in the mouth, where, ideally, we chew each bite thoroughly, allowing the enzyme-rich saliva to begin breaking down our food, signaling the nervous system to rest and digest, and alerting the rest of the digestive tract that it’s time to work.

Next stop is the stomach, which uses its powerful muscles to further mash the food while liquefying it with hydrochloric acid (HCl). The proper acidity digests the food for optimal nutrient absorption; sterilizes it by killing bacteria and other pathogens; and alerts the small intestine to open the pyloric valve and allow it in. Once there, the pancreas secretes enzymes and the gallbladder secretes bile to further digest the food.

Unfortunately, it’s estimated that 90 percent of Americans are deficient in stomach HCl due to stress, poor nutrition, bacterial overgrowth, poor thyroid function, and advancing age.

When the stomach environment is not acidic enough, the small intestine is not triggered to allow the food in, so it sits in the stomach, where it begins to ferment and putrefy. Eventually it may shoot back up into the esophagus, burning the tender tissue there and causing heartburn, or acid reflux.

The small intestine

Eventually the small intestine must accept the fermenting food. Because it is not the right acidity, the pancreas and gallbladder are not sufficiently triggered to release enzymes and bile to further digest it.

This is problematic for several reasons: Improperly digested fat irritates the rest of the digestive tract; nutrient absorption is poor, and the gallbladder is more prone to forming gallstones due to insufficient activity. Because it is the avenue through which the liver excretes toxins, a congested gallbladder results in a congested, overburdened liver unable to detoxify the blood properly.

As this poorly digested mess makes its way through the small and large intestines, it causes inflammation and damage that leads to intestinal permeability, or “leaky gut.” Leaky gut allows undigested food proteins to escape into the bloodstream, where the immune system attacks them, causing inflammation. Because undigested foods are the target of attack, food intolerances develop.

The colon

Our colons host 3 to 4 pounds of friendly bacteria, or gut flora. These bacteria break down foods and produce nutrients. However, breakdowns further north foster an overgrowth of bad bacteria, causing an inflamed, poorly functioning colon.

A properly functioning gastrointestinal tract produces between one to three bowel movements a day that are large, continuous and well formed, neither too soft nor too hard. If you are experiencing constipation, diarrhea, incomplete evacuation, or other issues with your bowel movements, you know something in the process described above has broken down.

All disease begins in the gut

While various drugs offer quick fixes for digestive complaints, they allow us to ignore the red flags the gastrointestinal tract is waving to gain our attention. Poor digestion underlies just about every disease known to man. This is a topic to which functional medicine practitioners devote their careers. Ask my office how we can better support your digestion to support your health.