Some experts have dubbed the digestive tract your "second brain" because it's so sensitive to your emotions.
Butterflies in your belly before giving a presentation. The burning in your chest when your boss lays a stack of work on your desk. Your stomach tied up in knots when you're stuck in traffic. Each of these physical reactions is evidence of the powerful connection between the mind and the gastrointestinal (GI) tract.
"We've observed this connection for hundreds of years," says Maxwell Chait, M.D., a gastroenterologist at Columbia Doctors Medical Group in Hartsdale, NY. "But we are just now scientifically proving the interrelationships." In fact, the connection between the brain and the gut is a two-way street.
Recent research suggests that the health of your digestive systemthe esophagus, stomach, small intestine and coloncan also affect your mood and well-being. One study from Stanford University showed that simply irritating the guts of newborn rats resulted in depression and anxiety-like behaviors and greater production of stress hormones, as compared with rats in a control group.
The key to the complex interaction is the enteric nervous system, which experts sometimes refer to as the "brain in your gut." "Thousands of nerves line the intestines and signal muscles to contract to propel food along the digestive tract," explains David Wolf, M.D., a gastroenterologist at the University of Texas Health Science Center in Houston. Like the one in your head, your gut's brain depends on neurotransmitters such as serotonin, the famous feel-good chemical.
"Around 95 percent of the body's serotonin is produced in the intestinal tract," says Dr. Chait. While the serotonin in your brain regulates mood, in the gut, it promotes the growth of nerve cells and alerts the immune system to foreign invaders like viruses and bacteria. Serotonin also keeps the two systems in constant communication, so when stress hits, it's no wonder your stomach starts to churnor that GI problems make you depressed and anxious.
New research is also highlighting the vital role of the healthy bacteria that exist naturally in the gut. Trillions of bacteria populate the gut, and scientists are only just beginning to understand this unique habitat, according to Jack Gilbert, Ph.D., an environmental microbiologist at the Argonne National Laboratory in Chicago. Dr. Gilbert is co-founder of the American Gut Project, an initiative in which Americans are contributing personal stool samples for scientists to study. When these good bacteria are diminished by, say, a poor diet or a course of antibiotics, your digestive health and overall well-being often suffer.
While there is more to know, doctors have learned plenty about how to keep the GI system in good working order. Here are a few DIY strategies:
The best way to improve your digestion is to eat a healthy, balanced diet, says Dr. Chait. Aim for plant-based, fiber-rich foodsplenty of vegetables and fruits, whole grains and bran, and lean sources of protein, such as chicken and fish.
Americans generally get well below the recommended amount of daily fiber38 grams for men under 50; 25 grams for women under 50; and 30 and 21 grams for men and women over 50, respectively.
Tackle your tension
Thanks to the enteric nervous system, the digestive system is very sensitive to emotional and psychological stress. Stress busters like deep breathing, yoga, meditation and massage can play an important role in alleviating GI disorders triggered or exacerbated by tension, such as irritable bowel syndrome (IBS), whose symptoms include cramping, bloating and often alternating bouts of constipation and diarrhea.
A recent study found that women who practiced mindfulness meditation for eight weeks had greater reductions in IBS symptoms than women who were assigned to a support group.
It's true: Regular exercise keeps you regular. Activity improves motilitythe movement of food through the digestive system. A recent Swedish study showed that when people with IBS became more physically active, their symptoms improved.
Pop a probiotic
These supplements restore the supply of good bacteria in the gut and may help if you have IBS, or anytime you're taking antibiotics, says Dr. Chait. Take a daily dose concurrently with your prescription and for another week afterward. And choose a formula that contains at least 5 billion CFUs (colony-forming units) of these beneficial organisms.
From our sister publication REMEDY's Healthy Living, Fall 2013