Gut-Brain Connection: What It Is and How It Affects Your Health
When the system is working well, it helps coordinate digestion, hunger and satiety, bowel rhythm, and the body’s response tostress, saysChristina Gentile, PsyD, a clinical health psychologist at UCLA Health. . .
When the system is working well, it helps coordinate digestion, hunger and satiety, bowel rhythm, and the body’s response tostress, saysChristina Gentile, PsyD, a clinical health psychologist at UCLA Health in Los Angeles, where she specializes in digestive diseases and the brain-gut connection. “A healthy gut-brain connection helps the body notice what matters, respond appropriately, and return to baseline. It also helps the brain filter normal digestive sensations, so that not every gurgle, shift, or movement in the gut is interpreted as a threat or treated as an alarm signal,” Dr. Gentile says. The gut-brain connection may affect:DigestionThe ENS controls functions ranging from the release of digestive enzymes to the blood flow needed for nutrient absorption. The gut also sends the brain information about fullness, nausea, and discomfort, Berry says. Bowel HabitsThe brain can change how quickly the intestines move. Stress may trigger diarrhea or an immediate need to have a bowel movement in some people, while contributing toconstipationin others, Berry says. But when the nervous system is calm, most digestive sensations stay in the background, Gentile says. Pain SensitivityIf you’re stressed or sick, or when your sleep, mealtimes, or daily routines are thrown off, you may notice symptoms like nausea, bloating, or abdominal pain, Gentile says. “A sensation that feels mild and manageable in one context may feel more intense, urgent, or harder to ignore when the gut is sensitive or the nervous system is on high alert,” she says. MoodGut health and mental health can influence each other, Gentile says. Digestive symptoms may affect anxiety, sleep, and energy, while anxiety and depression can also alter appetite, nausea, intestinal movement, and pain sensitivity. “Symptoms are real and biological even when stress or emotions are part of the pattern,” she says. Quality of LifeUnpredictable digestive symptoms may cause people to monitor their bodies closely, worry about finding a bathroom, or avoid eating, working, traveling, and socializing, Gentile says. “The burden is often greater when symptoms are chronic, painful, unpredictable, or embarrassing,” she adds. Research suggests people withirritable bowel syndrome (IBS)have poorer mental health and physical quality of life than the general population with GI-specific anxiety and depressive symptoms. Metabolism, Hunger, and Food PreferencesBy telling the brain how much a person has eaten and about incoming nutrients, the gut provides information used to regulate energy balance, blood sugar, and insulin sensitivity. Berry says gut-to-brain signaling may also influence cravings. Immune FunctionSeventy percent of the immune system sits in the gut, Berry says. Studies suggest that gut microbes may influence immune cells in both the GI tract and the brain, highlighting themicrobiome’srole in immune function.