Nutrition Updates

Wallace RB, Wactawski-Wende J, O'Sullivan MJ, Larson JC, Cochrane B, Gass M, and Masaki K. Urinary tract stone occurrence in the Women's Health Initiative (WHI) randomized clinical trial of calcium and vitamin D supplements. Am J Clin Nutr. 2011;94:270–277. Over the past several decades, incidence of kidney stones in women has increased by 37%. During this same period, calcium supplements, both with and without vitamin D, have been widely recommended for the prevention of osteoporotic fracture in women, and their use has become more common. However, long-term use of calcium and vitamin D has an impact on calcium absorption and excretion, and may affect urolithiasis. The finding of an increase in urinary tract stones among participants in the Women's Health Initiative (WHI) receiving calcium plus vitamin D supplements supports this theory. In an analysis reported by Wallace et al., other factors in the WHI were examined, including dietary, clinical, and participant factors, which may have contributed to the initial observation of increased incidence of urinary tract stones.