Fox A, Slater C, Ahmed B, et al. - Researchers examined patients undergoing bariatric surgery for the baseline and postsurgical prevalence of vitamin D deficiency. They performed assessment of 460 patients [mean (standard deviation) age: 48.0 (10.5) years; weight: 144.7 (27.3) kg; BMI 50.0 (7.6) kg/m²] who had undergone bariatric surgery in a university teaching hospital in North West England and had completed at least 12 months postoperatively. Among these patients, 292 (63.5%) underwent gastric bypass and 168 (36.5%) underwent sleeve gastrectomy. Whereas preoperatively, vitamin D deficiency and insufficiency were evident in 43.2% and 34.7%, respectively, deficiency and insufficiency were observed in 8.9% and 26.7%, respectively, at 12 months with similar trends up to 4 years of follow-up. Observations revealed prevalence of vitamin D deficiency and insufficiency presurgery. Postsurgery, these reduced significantly with routine supplementation.