J Am Coll Nutr. 2009 Oct;28(5):565-73. doi: 10.1080/07315724.2009.10719788.
Moderate weight loss alters bone turnover and reduces bone mineral density in overweight men and women. However, it is not known whether bone turnover is normalized during weight maintenance postweight loss. Thus, the objective of the present study was to examine changes in serum bone turnover markers during 9 months of weight maintenance following weight reduction on a very low-energy diet (VLED) in obese men and women.
Thirty-seven men (n = 13) and women (n = 24) aged 50 +/- 9.8 years underwent 3 months of weight reduction on a VLED ( approximately 500 kcal/d) followed by 9 months on either a low-carbohydrate or low-fat weight maintenance diet ( approximately 1600 kcal/d). Concentrations of osteocalcin (OC) and C-terminal peptide of type I collagen (CTX) in serum were measured using enzyme-linked immunosorbent assay at baseline and at months 3, 6, and 12. Serum parathyroid (PTH) concentrations were measured using a chemiluminescent immunoassay at all 4 time points. Data were analyzed using a 3-factor-repeated measures analysis of variance.
Average weight loss was 19% +/- 3% and, during the 9-month weight maintenance period, average weight gain was approximately 3%, with no differences due to diet composition. Serum concentrations of OC and CTX significantly increased after weight reduction and remained elevated during weight maintenance. Serum PTH was reduced after weight loss. Percent changes in OC and CTX were correlated during weight maintenance (r = -0.437, p = 0.008), but not during weight loss. Percent changes in CTX and body weight were negatively correlated during weight loss (r = -0.474, p = 0.003) and maintenance (r = -0.455, p = 0.006).
Weight loss induced via a VLED may result in an imbalance between bone formation and resorption and accelerate remodeling. The deleterious effect of energy restriction on bone remodeling rate appears to persist during weight maintenance.
适度的体重减轻会改变超重男女的骨转换并降低骨密度。然而，目前尚不清楚在减肥后的体重维持期间骨转换是否会恢复正常。因此，本研究的目的是在肥胖男女接受极低能量饮食（VLED）减肥 3 个月后，通过观察其在接下来的 9 个月体重维持期间血清骨转换标志物的变化，来检验这一情况。
37 名年龄在 50 ± 9.8 岁的男性（n = 13）和女性（n = 24）接受了为期 3 个月的 VLED（约 500 千卡/天）减肥，然后分别在低碳水化合物或低脂肪维持饮食（约 1600 千卡/天）上进行 9 个月的体重维持。在基线和第 3、6、12 个月时，采用酶联免疫吸附法测量血清骨钙素（OC）和 I 型胶原 C 端肽（CTX）的浓度。在所有 4 个时间点均采用化学发光免疫分析法测量血清甲状旁腺素（PTH）浓度。数据采用 3 因素重复测量方差分析进行分析。
平均体重减轻 19% ± 3%，在 9 个月的体重维持期间，平均体重增加约 3%，但与饮食组成无关。减肥后血清 OC 和 CTX 浓度显著升高，并在体重维持期间保持升高。减肥后血清 PTH 降低。在体重维持期间，OC 和 CTX 的百分比变化呈相关性（r = -0.437，p = 0.008），但在减肥期间无相关性。CTX 和体重的百分比变化在减肥期间（r = -0.474，p = 0.003）和维持期间（r = -0.455，p = 0.006）均呈负相关。
通过 VLED 诱导的体重减轻可能导致骨形成和吸收之间的不平衡，并加速重塑。能量限制对骨重塑率的有害影响似乎在体重维持期间仍然存在。
