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 1,602 practicing gastroenterologists. Broken out by city, gastroenterology doctor density in Agoura Hills is 3, in Alameda is 8, in Anaheim is 33, in Apple Valley is 5, in Arcadia is 13, in Bakersfield is 17, in Baldwin Park is 10, in Berkeley is 17, in Beverly Hills is 18, in Burbank is 18, in Burlingame is 5, in Chula Vista is 9, in Concord is 11, in Corona is 7, in Culver City is 8, in Daly City is 6, 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 2, in Fairfield is 4, in Fountain Valley is 13, in Fremont is 12, in Fresno is 33, in Fullerton is 9, in Garden Grove is 10, in Gilroy is 2, in Glendale is 18, in Hemet is 6, in Highland is 7, in Huntington Beach is 11, in Irvine is 26, in La Mesa is 12, in Laguna Beach is 3, in Laguna Hills is 10, in Lancaster is 17, in Livermore is 10, in Loma Linda is 26, in Long Beach is 31, in Los Alamitos is 11, in Los Angeles is 202, in Los Gatos is 3, in Manhattan Beach is 3, in Menlo Park is 2, in Mission Viejo is 18, in Modesto is 12, in Montebello is 8, in Monterey is 11, in Monterey Park is 14, in Mountain View is 13, in Murrieta is 10, in Napa is 4, in National City is 5, in Needles is 1, in Newport Beach is 23, in Novato is 3, in Oakland is 22, in Oceanside is 7, in Orange is 49, in Palm Springs is 7, in Palo Alto is 56, in Pasadena is 19, in Petaluma is 2, in Placentia is 5, in Pleasanton is 5, in Pomona is 6, in Poway is 8, in Rancho Mirage is 8, in Redwood City is 9, in Ridgecrest is 3, in Riverside is 16, in Roseville is 15, in Sacramento is 57, in San Clemente is 7, in San Diego is 114, in San Dimas is 4, in San Francisco is 99, in San Jose is 46, in San Luis Obispo is 7, in San Mateo is 7, in San Ramon is 9, in Santa Barbara is 10, in Santa Clara is 6, in Santa Cruz is 10, in Santa Maria is 6, in Santa Monica is 27, in Santa Rosa is 16, in Simi Valley is 8, in Stockton is 8, in Sunnyvale is 7, in Thousand Oaks is 11, in Torrance is 34, in Upland is 9, in Vacaville is 4, in Visalia is 4, in Walnut Creek is 28, in Whittier is 9, and in Yorba Linda is 2.

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.