Kalkwarf Heidi J, Khoury Jane C, Lanphear Bruce P
Division of General and Community Pediatrics, Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA.
Am J Clin Nutr. 2003 Jan;77(1):257-65. doi: 10.1093/ajcn/77.1.257.
Calcium supplements increase bone mass in children, but the effect does not persist once supplementation is discontinued.
The objective of this study was to determine whether milk intake during childhood and adolescence, when controlled for current calcium intake, is associated with adult bone mass (ie, bone mineral content), bone mineral density, and the incidence of osteoporotic fracture.
We used data from the third National Health and Nutrition Examination Survey of 3251 non-Hispanic, white women age >or=20 y. Bone density was measured at the hip. History of fracture of the hip, spine, or forearm was classified as a lifetime fracture (occurring after age 13 y) or an osteoporotic fracture (occurring after age 50 y). Subjects reported frequency of milk consumption during childhood (aged 5-12 y) and during adolescence (aged 13-17 y). Regression models controlled for weight, height, age, menopause and use of estrogen, physical activity, smoking, and current calcium intake.
Among women aged 20-49 y, bone mineral content was 5.6% lower in those who consumed <1 serving of milk/wk (low intake) than in those who consumed >1 serving/d (high intake) during childhood (P < 0.01). Low milk intake during adolescence was associated with a 3% reduction in hip bone mineral content and bone mineral density (P < 0.02). Among women aged >or=50 y, there was a nonlinear association between milk intake during childhood and adolescence and hip bone mineral content and bone mineral density (P < 0.04). Low milk intake during childhood was associated with a 2-fold greater risk of fracture (P < 0.05).
Women with low milk intake during childhood and adolescence have less bone mass in adulthood and greater risk of fracture.
钙补充剂可增加儿童骨量，但停止补充后效果不再持续。
本研究旨在确定在控制当前钙摄入量的情况下，儿童期和青春期的牛奶摄入量是否与成年后的骨量（即骨矿物质含量）、骨密度及骨质疏松性骨折的发生率相关。
我们使用了第三次全国健康与营养检查调查的数据，该调查涉及3251名年龄≥20岁的非西班牙裔白人女性。测量了她们髋部的骨密度。髋部、脊柱或前臂的骨折史被分类为终生骨折（13岁以后发生）或骨质疏松性骨折（50岁以后发生）。受试者报告了儿童期（5 - 12岁）和青春期（13 - 17岁）饮用牛奶的频率。回归模型对体重、身高、年龄、绝经情况和雌激素使用情况、体力活动、吸烟及当前钙摄入量进行了控制。
在20 - 49岁的女性中，儿童期每周饮用牛奶少于1份（低摄入量）的女性，其骨矿物质含量比每天饮用牛奶超过1份（高摄入量）的女性低5.6%（P < 0.01）。青春期牛奶低摄入量与髋部骨矿物质含量和骨密度降低3%相关（P < 0.02）。在年龄≥50岁的女性中，儿童期和青春期的牛奶摄入量与髋部骨矿物质含量和骨密度之间存在非线性关联（P < 0.04）。儿童期牛奶低摄入量与骨折风险增加2倍相关（P < 0.05）。
儿童期和青春期牛奶摄入量低的女性成年后骨量较少，骨折风险更高。
