Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
The hydrogen breath test is a test that uses the measurement of hydrogen in
the breath to diagnose several conditions that cause
gastrointestinal symptoms. In humans, only
bacteria - specifically,
anaerobic bacteria in the
colon - are capable of producing hydrogen. The bacteria produce hydrogen
when they are exposed to unabsorbed food, particularly sugars and
carbohydrates, not
proteins or
fats. Although limited hydrogen is produced from the small amounts of
unabsorbed food that normally reach the colon, large amounts of hydrogen may be
produced when there is a problem with the digestion or
absorption of food in the
small intestine, that allows more unabsorbed food to reach the colon.
Large amounts of hydrogen also may be produced when the colon bacteria move
back into the small intestine, a condition called
bacterial overgrowth of the
small bowel. In this latter instance, the bacteria are exposed to unabsorbed
food that has not had a chance to completely traverse the small intestine to be
fully digested and absorbed. Some of the hydrogen produced by the bacteria,
whether in the small intestine or the colon, is absorbed into the blood flowing
through the wall of the small intestine and colon. The hydrogen-containing blood
travels to the lungs where the hydrogen
is released and exhaled in the breath where it can be measured.
Abdominal pain is pain in the belly and can be acute or chronic. Causes include inflammation, distention of an organ, and loss of the blood supply to an organ. Abdominal pain can reflect a major problem with one of the organs in the abdomen such as the appendix, gallbladder, large and small intestine, pancreas, liver, colon, duodenum, and spleen.
Diarrhea is a change is the frequency and looseness of bowel movements. Cramping, abdominal pain, and the sensation of rectal urgency are all symptoms of diarrhea. Absorbents and anti-motility medications are used to treat diarrhea.
Gas or "intestinal gas" means different things to different people. Everyone has gas and eliminates it by belching or farting (passing it through the rectum).
Crohn's disease is a chronic inflammatory disease,
primarily involving the small and large intestine, but which can
affect other parts of the digestive system as well. Abdominal pain, diarrhea, vomiting, fever, and weight loss are
common symptoms.
In lactose intolerance, the digestive system cannot digest lactose (the main sugar in milk). Symptoms of lactose intolerance include diarrhea, flatulence, abdominal pain, abdominal bloating, abdominal distention, and nausea. There are several tests to diagnose lactose intolerance. Treatment is generally made with dietary changes, supplements, and adaptation to small amounts of milk.
IBS (irritable bowel syndrome) is a common gastrointestinal disorder involving abnormal gut contractions (motility) characterized by abdominal pain,
bloating, mucous in stools, and irregular bowel habits with alternating diarrhea
and constipation, symptoms that tend to be chronic and to wax and wane over the
years. Treatment options include medication and lifestyle changes such as diet, exercise, and stress management to control symptoms. Also called spastic colitis, mucus colitis, nervous colon syndrome.
Celiac disease is a result of an immune reaction to gluten, a protein found in wheat or related grains and present in many foods that we eat. Celiac disease causes impaired absorption and digestion of nutrients through the small intestine. Signs and symptoms of celiac disease include malabsorbption (diarrhea, foul smelling gas, bloating, and increased amounts of fat in the stool) and malnutrition (weight loss, edema, anemia, bruising easily, neuropathy, and infertility). Treatment for celiac disease is a gluten free diet, and at times if necessary, medications
Small intestinal bacterial overgrowth (SIBO) refers to a condition in which abnormally large numbers of bacteria (at least 100,000 bacteria per ml of fluid) are present in the small intestine and the types of bacteria in the small intestine resemble more the bacteria of the colon than the small intestine. There are many conditions associated with small intestinal bacterial overgrowth, to include: diabetes, scleroderma, Crohn's disease, and others. There is a striking similarity between the symptoms of irritable bowel syndrome and SIBO. It has been theorized that SIBO may be responsible for the symptoms of at least some patients with irritable bowel syndrome. Symptoms of SIBO include: excess gas, abdominal bloating, diarrhea, and abdominal pain.
Dyspepsia (indigestion) is a functional disease in which the gastrointestinal organs, primarily the stomach and first part of the small intestine, function abnormally. It is a chronic disease in which the symptoms fluctuate infrequency and intensity. Symptoms of dyspepsia include upper abdominal pain, belching, nausea, vomiting, abdominal bloating, early satiety, and abdominal distention (swelling). These symptoms are most often provoked by eating.
The inflammatory bowel diseases (IBD) are Crohn's disease (CD) and ulcerative colitis (UC). The intestinal complications of Crohn's disease and ulcerative colitis differ because of the characteristically dissimilar behaviors of the intestinal inflammation in these two diseases.
Digestion is the complex process of turning food you eat into the energy you need to survive. The digestive process also involves creating waste to be eliminated, and is made of a series of muscles that coordinate the movement of food.
The ability to belch is almost universal. Belching, also
known as burping (medically referred to as eructation), is the act of expelling gas from the stomach out through the
mouth. The usual cause of belching is a distended (inflated) stomach caused by
swallowed air. The distention of the stomach causes abdominal discomfort, and the
belching expels the air and relieves the discomfort. The common reasons for
swallowing large amounts of air (aerophagia) are gulping food or drink too
rapidly, anxiety, and carbonated beverages. People are often unaware that they
are swallowing air. "Burping" infants during bottle or
breastfeeding is important in order to expel air in
the stomach that has been swallowed with the formula or milk.
Excessive air in the stomach is not the only cause of belching. For some
people, belching becomes a habit and does not reflect the amount of air in their
stomachs. For others, belching is a response to an...