1. Chest Pain: Gastroesophageal Reflux Disease (GERD)

When stomach acid backs up into your esophagus — a condition called acid reflux — you may feel a burning pain in the middle of your chest. It often occurs after meals or at night, says Neville Bamji, MD, a clinical instructor of medicine at The Mount Sinai Hospital and a gastroenterologist with New York Gastroenterology Associates.
While it’s common for people to experience acid reflux and heartburn once in a while, having symptoms that affect your daily life or occur at least twice each week could be a sign of GERD, a
chronic digestive disease that affects 20 percent of Americans, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). If you experience persistent heartburn, bad breath, tooth erosion, nausea, pain in your chest or upper part of your abdomen, or have trouble swallowing or breathing, see your doctor.
Most people find relief by avoiding the foods and beverages that trigger their symptoms and/or by taking over-the-counter antacids or other medications that reduce stomach acid production and inflammation of the esophagus; however, some cases of GERD may require stronger medication or surgery.

2. Gallstones

Gallstones are hard deposits that form in your gallbladder — a small, pear-shaped sack that stores and secretes bile for digestion. Twenty million Americans are affected by gallstones, according to the NIDDK. Gallstones can form when there’s too much cholesterol or waste in your bile or if your gallbladder doesn’t empty properly. When gallstones block the ducts leading from your gallbladder to your intestines, they can cause sharp pain in your upper-right abdomen. Medications sometimes dissolve gallstones, but if that doesn’t work, the next step is surgery to remove the gallbladder.  

3. Celiac Disease

An estimated 1 in 133 Americans has celiac disease, according to the National Foundation for Celiac Awareness, but it’s also estimated that 83 percent of people who have celiac disease don’t know they have it or have been misdiagnosed with a different condition. Celiac disease is a serious sensitivity to gluten, a protein found in wheat, rye, and barley. Eat gluten, and your immune system goes on the attack: It damages your villi, the fingerlike protrusions in your small intestines that help you absorb nutrients from the foods you eat. Symptoms of celiac disease in kids include abdominal pain and bloating, diarrhea, constipation, vomiting, and weight loss. Symptoms in adults also can include anemia, fatigue, bone loss, depression, and seizures. However, some people may not have any symptoms. The only treatment for celiac disease is to completely avoid eating gluten. Common cooking alternatives to gluten include brown rice, quinoa, lentils, soy flour, corn flour, and amaranth.

4. Crohn’s Disease

Crohn’s disease is part of a group of digestive conditions called inflammatory bowel disease (IBD). Crohn’s most commonly affects the end of the small intestine called the ileum, but it can affect any part of the digestive tract. As many as 700,000 Americans may be affected by Crohn’s, according to the Crohn’s and Colitis Foundation of America. This chronic condition is an autoimmune disease, meaning that your immune system mistakenly attacks cells in your own body that it thinks are foreign invaders. The most common Crohn's symptoms are abdominal pain, diarrhea, rectal bleeding, weight loss, and fever. “Treatment depends on the symptoms and can include topical pain relievers, immunosuppressants, and surgery,” Dr. Bamji says.

5. Ulcerative Colitis

Ulcerative colitis is another inflammatory bowel disease that affects about 700,000 Americans. The symptoms are very similar to those of Crohn's, but the part of the digestive tract affected is solely the large intestine, also known as the colon. If your immune system mistakes food or other materials for invaders, sores or ulcers develop in the colon’s lining.If you experience frequent and urgent bowel movements, pain with diarrhea, blood in your stool, or abdominal cramps, visit your doctor. Medication can suppress the inflammation, and eliminating foods that cause discomfort may help as well. In severe cases, surgery is needed to remove the colon.

6. Irritable Bowel Syndrome

Is your digestive tract irritable? Do you have stomach pain or discomfort at least three times a month for several months? It could be irritable bowel syndrome (IBS), another common digestive condition. Ten to 15 percent of the U.S. population suffers from irritable bowel syndrome, according to the International Foundation for Functional Gastrointestinal Disorders. Signs of IBS can vary widely: You can be constipated or have diarrhea, or have hard, dry stools on one day and loose watery stools on another. Bloating is also a symptom of IBS. What causes IBS isn’t known, but treatment of symptoms centers largely on diet, such as avoiding common trigger foods (dairy products, alcohol, caffeine, artificial sweeteners and beans, cabbage, and other foods that produce gas), or following a low-fat diet that's also high in fiber. Friendly bacteria, such as the probiotics found in live yogurt, may also help you feel better. Stress can trigger IBS symptoms, so some people find cognitive-behavioral therapy or low-dose antidepressants to be useful treatments, as well.

7. Hemorrhoids

Bright red blood in the toilet bowl when you move your bowels could be a sign of hemorrhoids, which is a very common condition. In fact, 75 percent of Americans over the age of 45 have hemorrhoids, according to the NIDDK. Hemorrhoids are an inflammation of the blood vessels at the end of your digestive tract. They can be painful and itchy. Causes include chronic constipation, diarrhea, straining during bowel movements, and a lack of fiber in your diet. Treat this common digestive condition by eating more fiber, drinking more water, and exercising. Over-the-counter creams and suppositories may provide temporary relief of symptoms. See your doctor if at-home treatments don’t help. Sometimes hemorrhoids need to be removed surgically.

8. Diverticulitis

Small pouches called diverticula can form anywhere there are weak spots in the lining of your digestive system, but they are most commonly found in the colon. If you have diverticula but no symptoms, the condition is called diverticulosis, which is quite common among older adults and rarely causes problems; however, if the pouches bleed or become inflamed, it’s called diverticulitis. Symptoms include rectal bleeding, fever, and abdominal pain. Obesity is a major risk factor for diverticulitis. Mild diverticulitis is treated with antibiotics and a liquid diet so your colon can heal. A low fiber diet could be the cause of diverticulitis, so your doctor may direct you to eat a diet high in fiber — whole grains, legumes, vegetables — as part of your treatment. If you have severe attacks that recur frequently, you may need surgery to remove the diseased part of your colon.

9. Anal Fissure

Anal fissures are tiny, oval-shaped tears in the lining of the very end of your digestive tract called your anus. The symptoms are similar to those of hemorrhoids, such as bleeding and pain after moving your bowels. Straining and hard bowel movements can cause fissures, but so can soft stools and diarrhea. A high-fiber diet that makes your stool well formed and bulky is often the best treatment for this common digestive condition. Medications to relax the anal sphincter muscles as well as topical anesthetics and sitz baths can relieve pain; however, chronic fissures may require surgery of the anal sphincter muscle.