Low levels of serum calcidiol in an African population compared to a North European population

Objective: To compare vitamin D status in an African population living at 10 8N with a Norwegian population living at 60 8N. Design: Serum samples from 30 healthy young Ethiopians and 31 full term pregnant women from Addis Ababa were collected in September, and from 24 healthy Norwegians in March and 23 pregnant women from Oslo in February to June. Methods: Serum (s) levels of calcidiol and intact parathyroid hormone (iPTH) were measured. Results: The median values for s-calcidiol were significantly lower in Ethiopians compared with Norwegians (young Ethiopians 23.5 nmol/l vs young Norwegians 81 nmol/l, P < 0.001; pregnant Ethiopians 25 nmol/l vs pregnant Norwegians 36 nmol/l, P < 0.05) while those for s-iPTH were significantly higher (young Ethiopians 5.7 pmol/l vs young Norwegians 2.4 pmol/l, P < 0.001; pregnant Ethiopians 4.8 pmol/l vs pregnant Norwegians 2.8 pmol/l, P < 0.02). Conclusion: In spite of abundant availability of ultraviolet radiation, the population from Addis Ababa had a high rate of biochemical vitamin D deficiency compared with the Norwegian group.