Slim May, Vanstone Catherine A, Morin Suzanne N, Rahme Elham, Bacon Simon L, Weiler Hope A
School of Human Nutrition, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada.
Department of Medicine, Division of General Internal Medicine, McGill University, Montreal, Quebec, Canada.
J Nutr. 2022 Apr;152(4):1031-1041. doi: 10.1093/jn/nxab385. Epub 2023 Feb 18.
Adequate nutrition is important for bone health, especially for bone mineral accretion.
The primary objective tested whether increasing dairy intake using the motivational interviewing technique (MInt) improves lumbar spine (LS) bone mineral density (BMD) after 2 y in postpubertal adolescents with habitual dairy intake of <2 dairy servings/d.
Participants (aged 14-18.9 y) were randomly allocated to: group 1 (control), group 2 (target of 3 dairy servings/d), or group 3 (target of ≥4 dairy servings/d) for 12 mo, with groups 2 and 3 using MInt, with an additional 12-mo nonintervention follow-up. The primary outcome was LS BMD, and secondary outcomes were: whole body, total hip (TH), and 33% distal radius BMD using DXA, bone geometry using peripheral quantitative computed tomography, and bone biomarkers.
Ninety-four adolescents (16.6 ± 1.5 y) were recruited. Seventy-six (80.9%) completed the 12-mo assessments. From baseline to 12 mo, dairy intake in female groups 2 and 3 increased by 107% and 208%, respectively; and by 48% and 153% in males of groups 2 and 3, respectively. In females, group 3 had greater increases in TH BMD (4.3% to 7.5%) compared with control (3.7% to 4.9%, P = 0.04) and group 2 (0.0% to 1.7%, P = 0.04) at 12 and 24 mo. No effects due to dairy intake were observed for DXA outcomes in males for radial and tibial volumetric BMD in both sexes. None of the bone biomarkers were different among the dairy groups in females or males.
MInt effectively increased dairy intake with benefits to bone health only in female adolescents with previously low calcium intake who consumed ≥4 dairy servings/d for 12 mo. Larger studies are required to explain the lack of intervention effect in males.
充足的营养对骨骼健康很重要，尤其是对骨矿物质的积累。
主要目的是检验在习惯性每日乳制品摄入量少于2份的青春期后青少年中，采用动机性访谈技术（MInt）增加乳制品摄入量是否能在2年后改善腰椎（LS）骨密度（BMD）。
参与者（年龄14 - 18.9岁）被随机分配到：第1组（对照组）、第2组（目标为每日3份乳制品）或第3组（目标为每日≥4份乳制品），为期12个月，第2组和第3组采用MInt，并进行额外12个月的无干预随访。主要结局是LS骨密度，次要结局包括：使用双能X线吸收法（DXA）测量的全身、全髋（TH）和桡骨远端33%处的骨密度，使用外周定量计算机断层扫描测量的骨几何结构，以及骨生物标志物。
招募了94名青少年（16.6±1.5岁）。76名（80.9%）完成了12个月的评估。从基线到12个月，第2组和第3组女性的乳制品摄入量分别增加了107%和208%；第2组和第3组男性的乳制品摄入量分别增加了48%和153%。在女性中，第3组在12个月和24个月时全髋骨密度的增加幅度（4.3%至7.5%）大于对照组（3.7%至4.9%，P = 0.04）和第2组（0.0%至1.7%，P = 0.04）。在男性中，对于DXA测量的桡骨和胫骨体积骨密度，未观察到乳制品摄入量的影响。在女性或男性的乳制品组中，骨生物标志物均无差异。
动机性访谈技术（MInt）仅在之前钙摄入量低且每日摄入≥4份乳制品达12个月的女性青少年中有效增加了乳制品摄入量并有益于骨骼健康。需要更大规模的研究来解释男性缺乏干预效果的原因。
