Heartburn
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If youve never had heartburn before (other than after a spicy or super-sized meal) and youre suddenly experiencing burning on the regular without a specific trigger, its time to call your doctorespecially if you have other symptoms like weight loss, the feeling that food is getting stuck in your throat, or blood in your stool. You could be one of the estimated 20 percent of people , according to the National Institutes of Health (NIH), with gastroesophageal reflux disease (GERD), a condition where stomach acid causes inflammation and narrowing of the esophagus, says Marion. Since heartburn can lead to serious complications including ulcers and asthma, you shouldnt suffer in silencethe right medications usually nix symptoms.

Some people also confuse heartburn with chest pain, since the burn often hits between your chest and abdomen. Once people hit their forties, they take it more seriously. Severe heartburn can feel like angina, and it can be hard to distinguish the two, says Marion. Thats why its all the more important to see your doc and get checked if youre experiencing what feels like an unusual new bout of heartburn.

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Abdominal pain
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Abdominal pain can be tough to pinpoint. Even though your appendix is in your lower right abdomen, a lot of people have pain in their belly button when they have appendicitis, says Marion. Problems with your gallbladder, located just below your liver in the middle of your abdomen, can give you pain in your upper abdomen or even your back. Recurring abdominal pain could also be a sign of irritable bowel syndrome (IBS), which, according to the American College of Gastroenterology , is thought to affect 10 to 15 percent of Americans, although only 5 to 7 percent get diagnosed. Symptoms, which often include gas, diarrhea, and/or constipation, happen at least three times a month for three months or have been ongoing for at least six months.

When to talk to your doc depends on how long youve been feeling discomfort and how sharp the pain is. If its relatively new and not something you can associate with any change in your diet or lifestyle, if its keeping you from doing your daily activities and especially if associated with red-flag symptoms (more on that below), you should see your doctor after a couple of days, says Marion. Also check in if you have regular, ongoing pain, even if it passestheres often something your doc can do about it.

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Constipation
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Being constipated is not alarming, and theres no amount of bowel movements thats normal, says Jennifer Katz, M.D., Attending Physician at the Montefiore Medical Center Department of Gastroenterology in New York, NY. In fact, getting stopped up is one of the most common gastrointestinal problems, affecting an estimated 42 million Americans, according to the National Institutes of Health . Usually, constipationtaking a poop less than three times per week or having incomplete bowel movementsis caused by not getting enough fiber or a change in your routine or diet.

That said, constipation can sometimes be a sign of something more ominous, says Katz, which might include a thyroid problem, scarring or structuring from injury to the lining of the colon, IBS, or side effects from medications. If your BMs are interfering with the things you like to do, youre constantly running to the toilet to take a BM in installments, your stool is harder and requires straining, or youre using laxatives all the time to try and get things going, make an appointment, says Marion.

There are an amazing number of people who suffer in silence because theyre reluctant to bring it up with their doc, says Marion. There are many things we can do, like dietary changes or medications.

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Diarrhea
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Acute diarrhea, which lasts less than four weeks, is super common, with about 179 million cases happening every year, according to the NIH ; it can be caused by viral or bacterial infections, a parasite, or even eating too many sorbitol-containing foods (commonly found in sugar-free gum, sorbitol is also a common cause of gas). Since diarrhea can lead to severe dehydration fast, its important to see a doc if you have the runs with any of the following symptoms: loose stools for more than two days; a fever over 102 degrees F; frequent vomiting; six or more stools in 24 hours; severe pain in the abdomen or rectum; black, tarry, or blood/pus-containing stools; or symptoms of dehydration (thirst, sunken eyes, dark pee, peeing less than usual).

Chronic diarrhea, which happens on-and-off for at least one month, is less common. It could be caused by a thyroid issue, injury to the colon, medication side effects, a long-standing infection, Crohns disease, ulcerative colitis, IBS, celiac disease, or (rarely, and usually in older people) even canceralthough these tend to go hand-in-hand with red-flag symptoms. Or it might be a food allergy or intolerance to cows milk, soy, cereal grains, eggs, or seafood. The only way to know for sure is to talk to a doc. We want to find out exactly whats happening so we can treat problem from the source, says Marion.

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Uncomfortable bloating and gas
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Literally everyone gets gasbut some toot more than others. Maybe youve always been a little gassy for as long as you can remember, or maybe you rarely let one loose but have been super bloated for a week. If that discomfort keeps you from your normal routines, a good nutritionist and/or a gastroenterologist can help. It could be an anatomic problem like a stricture; inflammation related to IBS, Chrohns, or colitis; or a functional issue with what Marion calls the choreography or mobility of your bowel. You could even have recently developed a food allergy like lactose intolerance, which tends to crop up after the age of 30, celiac disease, or a bacterial overgrowth, adds Katz.

No matter the cause, its time to see your doctorespecially if gas is accompanied by signs like bleeding, weight loss, or recurrent vomitingto get tests to pinpoint the cause and medication to treat it if necessary. A dietitian may also want to check your diet to help you figure out if you should cut certain foods that might be making you balloon.

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Red-flag signs
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If any of your stomach problems are accompanied by the following symptoms, be sure to check in with your doctor right away:

Unexplained weight loss can be a sign of lots of conditions that need attention (like Crohns disease, ulcerative colitis, celiac disease, ulcers, depression, or, rarely, cancer). Other things to keep an eye on: fever, vomiting, no appetite or a change in appetite, blood in your stool or the feeling that food is getting stuck in your throat. These are all cases where youll want to get an explanation. Your doctor will give you a more invasive workup to get at the source of the problem, says Marion.