Feeling bloated? You’re not alone. Abdominal bloating and gas are among the most common digestive complaints that doctors hear from patients. And now there are new bloating culprits: COVID-19 and long COVID.
Belly bloating bothers some people largely because of how it looks. They may think a protruding tummy makes them look “pregnant.” Others are frustrated when that swollen stomach sticks around even after weight loss.
But for some people, it’s less about looks and more about discomfort. Not everyone experiences tummy bloating in the same way and symptoms can vary. Often, patients also describe belching or abdominal distension, as well as symptoms of acid reflux, says Dr. Charlotte Smith, an urgent care physician at Penn Medicine in Philadelphia.
If you’re ready to get rid of abdominal bloating, here’s what you should know.
What Is Stomach Bloating?
The terms bloating and abdominal distension are often used interchangeably. Technically, bloating is a temporary feeling of fullness, usually due to intestinal gas, while abdominal distension refers to a visible, measurable increase in the stomach’s size. Passing gas, belching or having a bowel movement may or may not provide relief.
Many people also experience heartburn, constipation or abdominal pain. Stomach bloating may persist hours after a meal. Food allergies, lactose intolerance and other digestive disorders could be bloating culprits.
Quite simply, you know it when you have stomach bloating. However to find out why, you and your doctor or dietitian need to do some detective work.
What Causes Tummy-Bloating Symptoms?
Dr. Hardeep Singh, a gastroenterologist with St. Joseph Hospital in Orange, California, says bloating can develop from several causes. Dietary problems are the most common, Singh says, with intolerance of certain food products leading the way. A food intolerance, or food sensitivity, means your digestive system can’t break down specific foods, which leads to excess gas and bloating. “Typical intolerances include dairy or gluten, but people can be intolerant to almost anything,” he says.
Beyond specific food triggers, swallowing air from eating too fast, chewing gum or using a straw is among the most common nutrition-related causes of bloating, says Cassie Vanderwall, a registered dietitian in the department of clinical nutrition at UW Health in Wisconsin.
Stomach bloating actually exacerbates a normal function of the stomach — expansion. Your stomach muscle is about the size of a fist at rest, but its muscular walls are designed to expand quite a bit to accommodate large amounts of food. Until the stomach completes its work of churning and breaking down food with digestive enzymes, it’s natural to feel temporarily full after a substantial lunch or supper. Therefore, one of the first steps in relieving bloating is to consume smaller portions that don’t force the stomach to expand so much all at once.
Farting and belching are also closely related to bloating. Belching or burping is caused by swallowed air that collects in the stomach. Passing rectal gas, or flatulence, is usually a combination of swallowed air and gas caused by bacteria in your colon forming around undigested carbohydrates.
Constipation can also cause bloating. If you’re bothered by a rock-solid stomach with abdominal pain that worsens through the day — and it’s relieved by pooping — constipation is the likely cause. With constipation, normal intestinal gas gets trapped behind a slow-moving poop and builds up.
Of course, a belly that isn’t perfectly flat can be perfectly normal. Sometimes, patients embarking on weight-management programs who don’t develop the six-pack abs they’ve been striving for may complain of bloating, when that’s not really an issue, Vanderwall notes, but more just stomach size overall.
Singh says other more serious potential causes of belly bloating include:
— Tumors in the stomach or intestine. Cancers of the stomach and intestine typically offer very few signs of their existence, but bloating related to constipation can be one.
— Intestinal blockage. Obstructions of the bowel can cause constipation, gas, bloating, cramping and abdominal pain.
— Inflammation of the stomach. Also called gastritis, inflammation of the lining of the stomach can have many sources, with bacterial infection related to ulcers being among the most common, the Mayo Clinic reports. Overuse of pain relievers and drinking too much alcohol can also cause gastritis.
— H. pylori infection. A common bacterium called Helicobacter pylori causes infection in the digestive tract and is related to peptic ulcers and stomach cancer. About 30% to 40% of people in the United States get an H. pylori infection sometime in their life, the National Institutes of Health reports. H. pylori infection is thought to be spread in multiple ways, such as drinking unsanitary water or by passing from person to person. It’s can be diagnosed with blood tests, stool cultures or an upper endoscopy exam.
— Tumors in the ovaries. As with tumors in the stomach and intestine, tumors in the female reproductive organs can also cause symptoms of bloating. Bloating that doesn’t resolve is one of the few noticeable symptoms of ovarian cancer.
— Fluid in the abdomen. Also called ascites, a buildup of fluid in the abdomen may be related to liver disease, cancer and heart failure.
— Stress and anxiety. With the brain-gut connection, continual stress and worry can affect digestive hormones and disrupt normal digestion. “Don’t underestimate the psychological impact on bloating,” says Smith, who has seen many patients with significant bloating and GI upset due to stress and anxiety alone.
Latest Bloating Contributor: COVID-19
COVID-19 infection can cause digestive problems.
“With active COVID, we have seen patients with some GI symptoms: nausea, vomiting, bloating and those kinds of things,” says Dr. Greg Vanichkachorn, director of Mayo Clinic’s COVID Activity Rehabilitation Program. That can happen with almost any viral illness, he notes, like the flu, “which can cause substantial stomach and digestive issues.”
Medications to treat active COVID-19 may contribute. “Some of the medicines we use can definitely affect the gut,” Vanichkachorn says. “Some antibiotics used early on for complicated infections can destroy the gut bacteria.” Steroids and other drugs can affect the GI system as well as the rest of the body, causing abdominal pain, bloating, constipation and food sensitivity.
Now, long COVID is creating persistent gastrointestinal woes. “What has been more surprising is that as we have gotten more into evaluating long COVID, we have seen that there are a fair number of patients who have been reporting ongoing GI problems,” Vanichkachorn says. “In some studies, 16% of patients report having new GI symptoms even 100 days or more after their infection, things like abdominal pain, constipation, vomiting and diarrhea. We’ve also heard about problems with excessive gas and the bloating sensation.”
Some patients with long COVID continue to experience GI symptoms for eight months and more on follow-up, according to an evidence review published in August 2022.
Which Foods Affect Bloating?
Some problem foods are more likely to cause bloating, while other foods help prevent it.
— Carbohydrates. Certain carbs are more likely to lead to abdominal discomfort. These difficult-to-digest carbs are known as FODMAPs, and “these complex carbohydrates in our diets are associated with gas and bloating,” Singh says. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols — saccharides refer to certain types of sugars and fiber. Basically, fermentable foods are easily broken down by bacteria in the bowel, leading to gas production. High FODMAP foods include wheat, garlic and onions.
— Fiber. Soluble fiber from processed, high-fiber cereals and snack foods may increase bloating. Although a soluble fiber called inulin is considered healthful, but it’s also been found to increase bloating and gas. Onions, garlic, wheat, bananas and some other fruits and veggies contain inulin. However, insoluble fiber, which doesn’t absorb water, may help relieve bloating. Bran, seeds and fruit and vegetable skins are prime sources of insoluble fiber, which speeds up food’s journey through the intestines and limits gas production.
— Sugars. Simple carbohydrates such as lactose or fructose and sugar alcohols, such as mannitol and xylitol (used to sweeten sugar-free candy and chewing gum) can trigger bloating. This is particularly likely in people with irritable bowel syndrome, a common digestive disorder. Foods that contain high fructose levels include corn syrup, certain fruits — such as apples, mangoes, watermelon, cherries and pears — and many sodas, snacks and condiments. Non-bloating fruits include most types of berries, pineapples, oranges and grapes. Using pure maple syrup as a sweetener may also cause less bloating than other sweeteners.
— Beans. It’s no myth: kidney beans, black beans, baked beans and others really do promote gas and bloating. Beans are a FODMAP food because they contain oligosaccharides and a lot of fiber, both of which can be difficult to digest, leading to gas and bloating.
— Fatty foods. Greasy, fatty foods, such as fried chicken, cheeseburgers, onion rings and french fries can make you feel bloated as they linger in your stomach. Indigestion results from eating high-fat foods — or just eating in excess overall, Vanderwall says.
— Excess salt or sodium. Foods high in salt — including many processed and convenience foods — can cause your body to retain fluid.
— Carbonated drinks. Drinking soda, particularly through a straw, can make you swallow excess air, and too much air in your intestines leads to bloating. However, by making you belch, fizzy drinks like seltzer might actually relieve pressure caused by gas buildup in the stomach.
Which Digestive Conditions Cause Bloating?
— Irritable bowel syndrome. IBS is a chronic condition that affects the large intestine. Abdominal pain, cramping, bloating, gas, diarrhea and constipation are all symptoms of IBS. The International Foundation for Gastrointestinal Disorders reports that IBS affects between 25 and 45 million people in the United States, and an estimated 10% to 15% of the population worldwide has IBS. Growing evidence supports the value of following a low-FODMAP diet to relieve irritable bowel syndrome. Consult a dietitian if you’re considering adopting a low-FODMAP diet.
— Lactose intolerance. Lactose, the sugar that’s mostly found in milk and dairy products, needs an enzyme called lactase to be digested. People whose bodies don’t produce enough lactase experience a range of abdominal symptoms — including bloating, nausea and diarrhea — after consuming foods containing lactose. A simple, noninvasive test called the hydrogen breath test can confirm lactase deficiency.
— Celiac disease. An intolerance to the protein gluten, called celiac disease, can cause noticeable bloating. Foods containing wheat, rye or barley, such as pasta, bread and flour, or beer, trigger an immune response affecting the small intestine in sensitive people. It can take up to a day or two for celiac-related belly bloating to deflate. Gas may be particularly foul-smelling. Fortunately, gluten-free foods have become much easier to find.
— Acid reflux. If your upper belly feels uncomfortably bloated, especially after eating, or you feel overly full or nauseated after a normal meal, acid reflux could be the cause. Burping excessively soon after eating is another sign of this type of indigestion. Acid reflux might be particularly bad after you eat a large, raw salad on an empty stomach, because of all the roughage. Gastroesophageal reflux disease, or GERD, is a possible cause of acid reflux.
Long COVID and Digestive Woes
New food sensitivities may arise in patients after COVID-19. “So they didn’t have any problems consuming, say, dairy products or, or have troubles with sugar,” “Vanichkachorn says. But afterward, they find themselves having a very limited diet that they can tolerate. We have some patients who are just eating Cheerios and yogurt and that’s all they can really stomach.”
Ongoing problems with taste and smell can also throw off patients’ appetites, he notes. “If we’re not careful, it can really get into a situation where they’re not eating enough and developing malnutrition, with electrolyte problems.”
Patients with long COVID describe a constellation of GI symptoms. “It can have a lot of functional impacts,” Vanichkachorn says. “I have some patients who, for example, have really severe, bloody stool, diarrhea and incontinence issues that keep them from leaving home and going to work.”
Figuring out how to treat COVID-related GI symptoms is an issue. “Most of the time we’ll start with things like a bland diet, probiotics and adequate hydration,” Vanichkachorn says. Probiotics may help promote the regrowth of healthy gut bacteria, he says, although patients’ results have been mixed. “But it’s worth a shot now.”
Such patients undergo a gastroenterology evaluation. “They go through testing like colonoscopies to see if there’s anything else going on, or testing to see if there are problems with how the gut moves because we’ve seen that occur in neuropathy issues, which we’ve also seen quite a bit with long COVID, too.”
Whether and when GI symptoms like bloating resolve are uncertain. “Some get resolution, but the patients I have right now who have these significant GI issues really seem to be not resolving with time,” Vanichkachorn says. “So I’m not comfortable telling people: OK, this is going to go away with time. I think we need to have more research on the GI illness for those with long COVID and hopefully develop some treatments.”
How Do Body Type and Weight Relate to Bloating?
Extra belly fat can contribute to bloating, even in an otherwise thin person. Possible culprits for excess abdominal fat include cigarette smoking and chronic alcohol consumption. Smoking affects where fat is deposited in the body, tending to favor the stomach. Heavy drinking has a similar effect, particularly in men. A so-called “beer gut” can really occur with any type of alcohol used in excess.
In women, having an apple-shaped body type means fat is more concentrated around the midsection, as opposed to pear-shaped body types. Obesity can be reduced with a healthy weight-loss plan. You’ll lose body fat all over, however, rather than just in your seemingly bloated midsection.
How Can You Get Rid of Bloating?
You don’t have to live with bloating, and there’s plenty you can do to alleviate bothersome or persistent symptoms.
— Keep a food journal. Pinpointing your personal bloating triggers is the first step. This should help you figure out which specific food triggers cause bloating, Singh says. Be precise about the foods you eat, the symptoms you experience and your bowel movements, including the times of day. Every detail matters, such as vitamins, alcohol and water intake, salad dressings and even midday treats like a piece of candy or two. This information will help your doctor or dietitian identify the cause of your bloating so you can make a plan to combat it.
— Eliminate possible food triggers. Once you’ve noticed a pattern, try removing the foods that appear to trigger bloating, one at a time, to see if gas and bloating improve. Look at labels to avoid ingredients that tend to bother you. Try temporarily cutting back on high-fiber foods that might boost bloating. With fiber, the key is to ramp up slowly when introducing it into your diet.
— Drink water. “I recommend increasing water intake as well as exercise to ease bloating in a lot of patients,” Smith says.
— Make related lifestyle changes. “Eliminate gum chewing and eat slower,” Singh says. If you’re an avid gum-chewer or hard-candy sucker, you’re more likely to swallow excess air. Quitting smoking and drinking alcohol more moderately should also help. Moving your body — try taking a walk after a meal — may relieve that feeling of fullness.
— Be mindful. Consider what could be causing your bloating and whether it’s tolerable or it’s time to make changes, Vanderwall says. A healthy, higher-fiber diet might be worth the trade-off in occasional bloating, for instance. However, she adds, if you believe that eating pace and food quantity are your problem, “this may be an area to explore and opportunity to become a more mindful eater.”
— Try bloating remedies. Over-the-counter products such as Mylanta Gas and Gas-X contain simethicone, which breaks down gas bubbles. Adding Beano, an over-the-counter supplement, to veggies and beans can prevent gas buildup. If you’re lactose-intolerant, enzyme supplements like Lactaid can improve your digestion.
— See a dietitian. “Registered dietitian nutritionists are well-prepared to accompany patients on their food- and nutrition-related journeys, including medical nutritional therapy for abdominal distension or bloating,” Vanderwall says.
— Visit your doctor. If bloating and related digestive problems persist, your health care provider may suggest certain tests to rule out medical conditions. “Routine labs including testing for H. pylori infection or celiac disease should be considered,” Singh says, and if indicated, your doctor may recommend an abdominal ultrasound or endoscopy to have a look at what’s happening inside your belly. In some cases, antibiotics can relieve bloating from bacterial overgrowth.
It’s possible that serious medical conditions may be the underlying cause of bloating, so the bottom line is: If issues persist, see a gastroenterologist, he says.
“People need to realize that this is not normal,” Vanichkachorn emphasizes. “So if patients are worried about any symptom, whether it may be related to COVID or not, they should go ahead and try to find care.”
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Stomach Bloating: How to Relieve Your Tight, Round Belly originally appeared on usnews.com
Update 09/23/22: This story was previously published at an earlier date and has been updated with new information.