Could the bloating or discomfort you feel after eating or drinking be a sign that something in your intestinal tract is amiss?
Here are 15 questions people have about what’s going on inside their guts, with answers from some leading experts in nutrition and gastroenterology.
1) How can I tell if my gut is healthy?
The simplest sign of a smoothly running gastrointestinal tract is also the most boring one: your gut should chug along quietly with little complaint. Eating or drinking should not cause more than occasional bloating or discomfort and you should have regular, well-formed bowel movements every one to three days that pass without much straining, said Dr Folasade May, a gastroenterologist and associate professor of medicine at the David Geffen School of Medicine at UCLA.
If you regularly have discomfort or pain from symptoms such as acid reflux, bloating, constipation or diarrhea, that could be a sign that your gut is not working optimally, Dr May said. And it might be worth thinking about whether simple tweaks to your diet and other lifestyle factors would help.
If your symptoms persist or affect your quality of life, you should see a doctor or a gastroenterologist, Dr May said. And seek care right away if you have what she called “red flag” symptoms such as nausea and vomiting, recurrent abdominal pain, infrequent or painful stools, or blood in your stool – these symptoms could indicate a serious condition, like an infection, inflammatory bowel disease or even cancer.
2) How does my gut affect the rest of my body?
Aside from your gut’s obvious job of digesting food and absorbing nutrients, research has shown that the trillions of bacteria, viruses and fungi that inhabit your intestinal tract (also known as the gut microbiome) can “influence virtually all aspects of our biology,” said Justin Sonnenburg, a professor of microbiology and immunology at Stanford Medicine.
Much of your immune system resides in your gut, for example, and its resident microbes influence how that system functions, he said. Your gut microbes produce a variety of small molecules that have been shown to affect metabolism, inflammation and appetite, with possible links to certain diseases including obesity, heart disease and even some types of cancer.
“The gut also influences what’s happening in the brain,” said Dr William Chey, a professor of gastroenterology and nutritional sciences at Michigan Medicine. One study published in 2016, for example, found that transferring gut microbes from humans with depression into rats induced depressive and anxious behaviours in the rodents. Some human studies have also shown that taking certain gut bacteria such as probiotic supplements may improve anxiety and depression, but it’s too early to recommend probiotics to improve mental health, Dr Chey said.
Consuming a variety of plant-based foods can also help to diversify the types of microbes in your gut, which is associated with better health
— Emily Haller
3) What are some simple things I can do to improve my gut health?
Unsurprisingly, the best way to care for your gut is to feed yourself – and by extension, your gut microbes – well. Prioritising foods rich in fibre (such as vegetables, whole grains, nuts, seeds, beans and lentils) is one main way to boost gut health because fibre is an important source of nutrients for those bacteria, said Emily Haller, a registered dietitian nutritionist at Michigan Medicine.
Consuming a variety of plant-based foods can also help to diversify the types of microbes in your gut, which is associated with better health, Haller said. One study published in 2018, for instance, found that people who ate more than 30 types of plant foods per week had a more diverse gut microbiome than those who ate up to 10 types of plant foods per week.
Adding more fermented foods such as yoghurt, kefir, kombucha, sauerkraut or kimchi to your diet can also be a safe (and tasty) way to boost the diversity of your microbiome and decrease inflammation, Prof Sonnenburg said. Though more research is needed to confirm those links and to determine how much fermented food you must eat to obtain those benefits.
4) Are there any foods I should limit for the sake of my gut health?
Generally speaking, highly-processed foods tend to contain little fiber for gut microbes to eat. Some processed foods also contain certain synthetic emulsifiers (added to improve texture and shelf life) that have been shown in studies with mice and limited human studies to harm the gut by reducing the diversity of the gut microbiome, degrading the gut lining and increasing inflammation, said Jens Walter, a professor of ecology, food and the microbiome at University College Cork.
Alcohol as well as processed and red meats have also been associated with a greater risk of colorectal cancer, so it’s best to limit them, health experts say. But don’t stress about the occasional hot dog or beer, Haller said. What’s more important is to make sure that what you eat overall, “for days and weeks and years”, contains more whole plant foods and less processed foods. That “really is going to have the strongest impact on our health, including gut health,” she said.

Over-the-counter medications such as antacids, histamine-2 blockers and proton pump inhibitors can help manage reflux symptoms, Dr Chey said. Photograph: Daniel Acker/Bloomberg
5) I often feel heartburn after I eat. Why is that?
When the sphincter muscle that connects the bottom of your oesophagus to your stomach opens more than it should and allows too much stomach acid to enter, or if acid from your stomach lingers in your oesophagus for too long, that can cause heartburn or other symptoms of acid reflux, said Dr Rena Yadlapati, a gastroenterologist and associate professor of clinical medicine at the University of California, San Diego. Some people have more s