title: Vitamin D status in gastrointestinal and liver disease.
abstract: OBJECTIVE
  The purpose of this review is to report on the vitamin D status and its relationship with bone health in individuals with gastrointestinal and liver disorders. In addition, recommendations regarding replacement and maintenance of optimal vitamin D stores, as well as the state of knowledge regarding its effect on the disease through its actions on the immune system, will be reviewed.
  
  
  RESULTS
  The scientific community has revised upward the serum levels of vitamin D considered optimal, and doses of vitamin D much larger than those currently recommended may be needed to maintain these levels, especially in individuals with gastrointestinal and liver disorders. The relationship between vitamin D and bone health in this population is controversial. The role of vitamin D in the regulation of the immune system continues to be elucidated.
  
  
  CONCLUSIONS
  Hypovitaminosis D is prevalent among individuals with gastrointestinal and liver disease. Although replacement and supplementation guidelines have not been well defined, practitioners should aim for a serum 25-hydroxyvitamin D level of at least 32 ng/ml. The contribution of vitamin D to the bone health of these individuals and its role in altering disease course through its actions on the immune system remain to be elucidated.
authors.affiliation: Division of Gastroenterology and Nutrition, Department of Medicine, and General Clinical Research Center, Children's Hospital Boston, Boston, Massachusetts, USA.
authors.forename: Helen M
authors.initials: HM
authors.lastname: Pappa
authors.forename: Elana
authors.initials: E
authors.lastname: Bern
authors.forename: Daniel
authors.initials: D
authors.lastname: Kamin
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Grand
mesh_terms: D001847:Bone Diseases / Q000209:etiology / Q000517:prevention & control; D004066:Digestive System Diseases / Q000150:complications*; D005767:Gastrointestinal Diseases / Q000150:complications; D006801:Humans; D007107:Immune System / Q000187:drug effects; D007154:Immune System Diseases / Q000209:etiology; D008107:Liver Diseases / Q000150:complications; D014807:Vitamin D / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000097:blood / Q000502:physiology*; D014808:Vitamin D Deficiency / Q000097:blood / Q000188:drug therapy / Q000209:etiology
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D