Gastroenterology is the study of the gastrointestinal (GI) tract of the body. A gastroenterologist diagnoses and treats diseases of the digestive organs, including the stomach, esophagus, intestines, pancreas, liver and gallbladder. This specialist treats conditions such as abdominal pain, nausea and vomiting, ulcers, diarrhea, cancer in the GI tract, and jaundice. A gastroenterologist also performs complex diagnostic procedures, including the use of endoscopes to see and treat internal organs.

Physicians in this specialty treat patients suffering from numerous diseases and illnesses, but some of the most common are Hemorrhoids, Hiatal Hernia, Digestive Disorders, heartburn, Rectal Bleeding, Ulcer, Ostomy Care, Polyps, colon cancer, Crohn's Disease, Diarrhea, Abdominal Pain, Constipation, acid reflux, Bowel Diseases, cystic fibrosis, Ulcerative Colitis, Nausea, Appendicitis, and Colitis.

Once properly diagnosed, practitioners can perform numerous procedures on patients including GERD Services, abdominal surgery, Appendectomy, Cholecystectomy, laparoscopy, Liver Transplantation, and Cholecystography.

To diagnose patients with possible illnesses and diseases, specialists will often perform one of many tests including endoscopy, Colonoscopy, Barium Enema, Liver Biopsy, Sigmoidoscopy, Barium Swallow, Abdominal Ultrasound, Esophagogastroduodenoscopy (EGD), Gallbladder Scan, Upper Gastrointestinal Series, Endoscopic Retrograde Cholangiopancreatography, Radiographic X-Ray, Proctoscopy, Pancreas Scan, Abdominal Angiogram, Anoscopy, Liver Scan, and Abdominal X-rays.

Doctor density varies by specialty and location. California has 1,600 practicing gastroenterologists. Broken out by city, gastroenterology doctor density in Agoura Hills is 3, in Alameda is 8, in Anaheim is 29, in Apple Valley is 5, in Arcadia is 12, in Bakersfield is 18, in Baldwin Park is 10, in Berkeley is 17, in Beverly Hills is 16, in Burbank is 17, in Burlingame is 5, in Chula Vista is 8, in Concord is 11, in Corona is 6, in Culver City is 10, in Daly City is 7, in Duarte is 4, in El Cajon is 4, in El Monte is 1, in Encinitas is 5, in Escondido is 4, in Eureka is 3, in Fairfield is 4, in Fountain Valley is 11, in Fremont is 14, in Fresno is 35, in Fullerton is 7, in Garden Grove is 11, in Gilroy is 2, in Glendale is 15, in Hemet is 6, in Highland is 7, in Huntington Beach is 9, in Irvine is 27, in La Mesa is 12, in Laguna Beach is 2, in Laguna Hills is 10, in Lancaster is 18, in Livermore is 7, in Loma Linda is 26, in Long Beach is 30, in Los Alamitos is 10, in Los Angeles is 196, in Los Gatos is 3, in Manhattan Beach is 2, in Menlo Park is 2, in Mission Viejo is 17, in Modesto is 14, in Montebello is 3, in Monterey is 11, in Monterey Park is 15, in Mountain View is 13, in Murrieta is 11, in Napa is 4, in National City is 4, in Needles is 1, in Newport Beach is 23, in Novato is 3, in Oakland is 22, in Oceanside is 7, in Orange is 44, in Palm Springs is 8, in Palo Alto is 59, in Pasadena is 19, in Petaluma is 2, in Placentia is 4, in Pleasanton is 4, in Pomona is 6, in Poway is 8, in Rancho Mirage is 10, in Redwood City is 9, in Ridgecrest is 3, in Riverside is 17, in Roseville is 15, in Sacramento is 63, in San Clemente is 6, in San Diego is 111, in San Dimas is 5, in San Francisco is 103, in San Jose is 44, in San Luis Obispo is 8, in San Mateo is 7, in San Ramon is 8, in Santa Barbara is 10, in Santa Clara is 7, in Santa Cruz is 10, in Santa Maria is 6, in Santa Monica is 29, in Santa Rosa is 17, in Simi Valley is 8, in Stockton is 8, in Sunnyvale is 7, in Thousand Oaks is 12, in Torrance is 36, in Upland is 8, in Vacaville is 3, in Visalia is 5, in Walnut Creek is 26, in Whittier is 10, and in Yorba Linda is 1.

California’s population is 36,142,137, and it is America’s third largest and most populous state. It also claims the highest and lowest altitudes in the lower 48 states. The lowest point in the country, Death Valley, is also home to the nation’s highest recorded temperature, 134 degrees. Tourists flock to this state for its many outdoor activities and attractions, including Universal Studios, Disneyland, Rodeo Drive shopping, the Golden Gate Bridge in San Francisco, wine country tours, and California’s numerous beaches and parks. Los Angeles is the nation’s second largest city, but California’s capital is Sacramento. The giant sequoias in California’s forests are among the oldest living things in the world, and a redwood in the Redwood National Park is said to be the world’s tallest tree, at 365 feet. California achieved statehood in 1850, and was named the Golden State after the beginning of the Gold Rush in 1848.

According to 2005 Census estimates, California has a population of 36,132,147. Of this population, 9,308,563 are under the age of 18 and 3,827,038 are at or above the age of 65.