Nutritional Regulation of bone

骨骼的营养调节

• 批准号: 7475754
• 负责人: Sue Amy Shapses
• 金额: $ 29.69万
• 依托单位: RUTGERS, THE STATE UNIV OF N.J.
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-30 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7475754
• 关键词: Acids; Address; Adult; Affect; Age; Attenuated; Biological Markers; Body Weight decreased; Bone Density; Bone Resorption; Calcium; Caloric Restriction; Calories; Carbohydrates; Chronic; Data; Diet; Dietary Calcium; Dietary Proteins; Estrogens; Fat-Restricted Diet; Fatty acid glycerol esters; Fracture; Goals; High Prevalence; Hormones; Insulin-Like Growth Factor I; Insulin-Like Growth-Factor-Binding Proteins; Intake; Knowledge; Metabolic; Nutritional; Obesity; Older Population; Osteoporosis; Osteoporosis prevention; Outcome; Parathyroid Hormones; Placebos; Population; Postmenopause; Prevention; Procedures; Proteins; Public Health; Recommendation; Regulation; Risk; Role; Serum; Somatomedins; Standards of Weights and Measures; Stomach; Trochanters; Vitamin D; Weight; Woman; YARS gene; absorption; bariatric surgery; bone; bone health; bone loss; bone quality; bone turnover; calcium metabolism; day; human PTH protein; hypercalciuria; improved; interest; moderate obesity; mortality; prevent; weight maintenance

DESCRIPTION (provided by applicant): Osteoporosis and obesity are both important public health problems. Weight (wt) reduction is recommended to reduce obesity-related complications, but induces bone loss (even with adequate Ca intake) in post- menopausal women. Although several studies have begun to address the effects of diet composition during caloric restriction (CR) on metabolic parameters, virtually nothing is known its role on bone mass and quality. This proposal will address several major gaps in our knowledge concerning dietary composition during wt loss as it impacts bone health. In particular we will address dietary protein (pro) levels, and the role of vitamin D (vit D) in Ca absorption. Evidence in wt-stable adults shows that higher dietary pro increases insulin-like growth factor-1 and Ca absorption and may contribute to a higher bone mass and reduced fracture risk. In contrast, a high pro intake has also been shown to increase the acid load, leading to hypercalciuria, and potential bone loss. It is currently not known how a high pro diet affects bone density or quality during CR. In addition, the level of pro intake may be especially important during severe wt loss after gastric bypass surgery (GB), because of the deficient pro intake (rather than Ca and vit D) that typically follows the procedure that may exacerbate bone loss. Furthermore, because serum parathyroid hormone (PTH) explains part of the reduction in Ca absorption observed during CR (400IU vit D /day), it is possible that increasing serum 25-hydroxy-vit D levels through diet will attenuate serum PTH and enhance true fractional Ca absorption (TFCA). The aims of this proposal are: 1) to examine how a high-pro diet compared to a standard high-carbohydrate (HC) wt loss diet affects bone turnover, mass and quality in post- menopausal women, while controlling for normal Ca and vit D intake; 2) to examine bone with usual and higher pro intake during severe wt loss in women with GB; and 3) to determine if a high vit D intake (1200 lU/d) can increase TFCA in postmenopausal women during a standard HC wt-loss diet. Overall, rationale recommendations for the prevention of bone loss are needed for nearly % of the US population that is regularly dieting. The older population is going to double in only a few decades, and wt loss is a major determinant of bone loss, fracture risk, and ultimately mortality. Thus, the importance of these studies for identifying how diet composition can prevent bone loss in the older population is both critical and timely.

描述（由申请人提供）：骨质疏松症和肥胖症都是重要的公共卫生问题。建议减轻体重（wt）以减少肥胖相关并发症，但会导致绝经后女性骨质流失（即使摄入足够的钙）。尽管一些研究已经开始探讨热量限制 (CR) 期间饮食成分对代谢参数的影响，但实际上对其对骨量和骨质量的作用尚不清楚。该提案将解决我们在体重损失期间膳食成分的知识中的几个主要空白，因为它会影响骨骼健康。我们将特别讨论膳食蛋白质 (pro) 水平以及维生素 D (vit D) 在钙吸收中的作用。体重稳定成年人的证据表明，较高的饮食 Pro 会增加胰岛素样生长因子 1 和 Ca 的吸收，并可能有助于增加骨量并降低骨折风险。相比之下，大量的前体摄入量也被证明会增加酸负荷，导致高钙尿症和潜在的骨质流失。目前尚不清楚高营养饮食如何影响 CR 期间的骨密度或质量。此外，在胃绕道手术 (GB) 后严重体重减轻期间，前体摄入水平可能尤其重要，因为手术后通常会出现前体摄入不足（而不是钙和维生素 D），从而可能加剧骨质流失。此外，由于血清甲状旁腺激素 (PTH) 解释了 CR（400IU 维生素 D/天）期间观察到的 Ca 吸收减少的部分原因，因此通过饮食增加血清 25-羟基维生素 D 水平可能会减弱血清 PTH 并增强真实钙吸收分数 (TFCA)。该提案的目的是：1) 检验与标准高碳水化合物 (HC) 减重饮食相比，高蛋白饮食如何影响绝经后女性的骨转换、质量和质量，同时控制正常的钙和维生素D摄入量； 2) 检查患有 GB 的女性在严重体重损失期间的正常摄入量和较高的 Pro 摄入量； 3) 确定高维生素 D 摄入量（1200 lU/天）是否可以在标准 HC 减重饮食期间增加绝经后妇女的 TFCA。总体而言，近 % 定期节食的美国人口需要预防骨质流失的合理建议。老年人口将在短短几十年内翻一番，而体重损失是骨质流失、骨折风险和最终死亡率的主要决定因素。因此，这些研究对于确定饮食成分如何预防老年人骨质流失的重要性既关键又及时。