Today, one out of every 10 Americans is taking a drug for depression or anxiety. We spend billions of dollars every year just to cope with these issues… and still people are sad and stressed. It is clear that popping purple pills hasn’t fixed the problem.
Many people blame our crazy modern life. People feel less connected to others, despite computers and the internet. We have road rage, cell phones, time pressures and money worries. This stress can lead to depression. But stress has always been a part of our lives. Think about the stress our ancestors were under to find food, keep warm in winter, or not get eaten.
Something other than our modern life is causing us to feel sad and anxious, but what?
Scientists are asking this question and what they have found may come as a surprise. The last place you might think to look for the source of mental and emotional problems is in the gut. But scientists have found that the bacteria and other microorganisms in our digestive tracts (known as our gut flora) may be part of the reason we feel depressed and anxious.
The Gut Brain Axis
The first step in understanding how our gut flora can affect our mood is to understand the gut/brain axis.
Doctors of old used to focus on the body as a whole. But around the 1950s, the medical profession began to focus on specialties. The brain, they thought, is different from the heart. The heart is different from the liver. And the liver is different from the lungs.
This may be true. But they forgot that all systems within the body are connected. The heart communicates with the brain. And the brain communicates with the heart. This is also true of the gut and the brain.
Scientists have found more connections between the gut and the brain than they ever thought possible. They even use some of the same chemical messengers (called neurotransmitters). Serotonin is just one of these. It has been called the “feel good” neurotransmitter for its effects on mood and happiness.
But did you know that over 90 percent of the serotonin in the body is actually found in the digestive tract? It not only helps digestion, but it is also used to send messages from the gut to the brain.
Have you ever felt “butterflies” before speaking in front of a group of people? Have you ever known something was wrong by a “gut feeling?” Or have you ever felt “sick to your stomach” due to fear or emotional stress? If so, then you know how real this connection can be.
Serotonin is the reason for most of these feelings. The connections between the digestive system and the brain are now so clear that some scientists call the gut, the “second brain.”
And the connection shows up in other ways. Most people with anxiety and depression suffer from digestive problems. In fact, many people with irritable bowel syndrome also suffer from depression.1
The connection between the gut and the brain is one thing. But scientists were shocked to learn that the bacteria in your gut may also play a role in how you feel mentally and emotionally.
The Gut Flora
You’ve certainly heard about probiotics – the friendly bacteria that live in our gut. These good bugs help us digest foods. They release vitamins and nutrients that nourish our bodies. They are also responsible for a large part of our immunity.
But you might be surprised to learn just how many bacteria we have. Estimates are that the average person has around 100 trillion bacteria in their gut. Now compare that to the 10 trillion or so cells in the human body. That means there are as much as 10 times more bacteria in your gut than there are cells in your body.
When scientists give animals (mostly mice) probiotics, they can measure changes in their brain chemistry.2 Some of these changes are related to a brain chemical called GABA. Increases in GABA are related to reduced anxiety and depression.
Since it worked in animals, scientists began to wonder if probiotics could change the brain chemistry of humans. Two recent studies took up this challenge.
The first study used people who suffer from chronic fatigue syndrome. The researchers gave half of these subjects a probiotic supplement for two months. The other half of the group was given a placebo. When tested before and after the treatment, the group that received the probiotic showed less depression and anxiety.3
In another study, researchers gave volunteers a probiotic, a placebo, or nothing for one month. Then they scanned the brains of these volunteers. The subjects who took the probiotic showed better responses to stress.4
Connecting the Dots
These results should not be surprising. Our guts are closely connected to our brains. This is something we all feel. And while this research is new, it is exciting to think that taking probiotics will not only improve your digestion and raise your immunity… it can also make you feel better and lower your levels of stress.[Ed. Note: If you’re looking for solutions to cope with chronic stress and other concerns that can accelerate aging, then you should know about two important minerals that promote relaxation and calmness… And which common foods to avoid that may be elevating your stress hormones. Plus, you’ll learn what probiotics are best, a simple trick for better sleep, and other simple ways to start feeling and looking younger right now.]
1Hartono JL, Mahadeva S, Goh KL. Anxiety and depression in various functional gastrointestinal disorders: do differences exist? Journal of Digestive Diseases. 2012 PMID: 22500787.
2Bravo JA, Forsythe P, Chew MV, et al. Ingestion of Lactobacillus strain regulates emotional behavior and central GABA receptor expression in a mouse via the vagus nerve. Proceedings of the National Academy of Science U S A. 2011 Sep 20;108(38):16050-5. PMID: 21876150.
3 Rao AV, Bested AC, Beaulne TM, et al. A randomized, double-blind, placebo-controlled pilot study of a probiotic in emotional symptoms of chronic fatigue syndrome. Gut Pathology. 2009 Mar 19;1(1):6. PMID: 19338686.
4Tillisch, K. Modulation of the Brain-gut Axis After 4-week Intervention with a Probiotic Fermented Dairy Product (Abstract #589) presented at Digestive Disease Week Conference, May 21, 2012, San Diego Convention Center.