Proceedings of the Nutrition Society

Meeting Report

Is vitamin A consumption a risk factor for osteoporotic fracture?

Margo E. Barkera1 c1 and Aubrey Blumsohna1

a1 Human Nutrition Unit1 and Bone Metabolism Unit2, Division of Clinical Sciences (North), University of Sheffield, Northern General Hospital, Herries Road, Sheffield S5 7AU, UK

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.

Correspondence:

c1 *Corresponding author: Dr Margo E. Barker, fax +44 114 261 0112, m.e.barker@sheffield.ac.uk