title: Is vitamin A consumption a risk factor for osteoporotic fracture?
abstract: Severe vitamin A toxicity is known to have adverse effects on skeletal health. Studies involving animal models and case reports have documented that hypervitaminosis A is associated with bone resorption, hypercalcaemia and bone abnormalities. More recently, some epidemiological studies have suggested that high habitual intake of vitamin A could contribute to low bone mineral content and fracture risk. The evidence relating to the possible deleterious role of vitamin A in bone health is of variable quality and is potentially confounded by collinearity of nutrient intake and difficulties in assessing vitamin A exposure. Furthermore, because intake of vitamin A varies between studies it is not possible to define an intake threshold associated with harm.
authors.affiliation: Human Nutrition Unit, Division of Clinical Sciences (North), University of Sheffield, Northern General Hospital, Herries Road, Sheffield 55 7AU, UK. m.e.barker@sheffield.ac.uk
authors.forename: Margo E
authors.initials: ME
authors.lastname: Barker
authors.forename: Aubrey
authors.initials: A
authors.lastname: Blumsohn
mesh_terms: D000818:Animals; D015519:Bone Density / Q000187:drug effects*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D050723:Fractures, Bone / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D006986:Hypervitaminosis A / Q000150:complications* / Q000503:physiopathology; D010024:Osteoporosis / Q000209:etiology*; D012307:Risk Factors; D014801:Vitamin A / Q000008:administration & dosage* / Q000009:adverse effects / Q000502:physiology
chemical_list: D014801:Vitamin A