title: Effect of Milk Powder Supplementation with Different Calcium Contents on Bone Mineral Density of Postmenopausal Women in Northern China: A Randomized Controlled Double-Blind Trial.
abstract: The objective of this study is to examine the effect of milk powder supplementation with different calcium contents on bone mineral density (BMD) in postmenopausal Chinese women, and to determine a more appropriate dose of calcium supplementation. A 2-year, randomized controlled double-blind trial. Postmenopausal women (n = 210) aged 50-65 years were recruited and assigned randomly into three calcium supplementation groups. All participants received milk powder supplementation with different calcium contents (300, 600, and 900 mg per day for groups A, B, and C, respectively) and all groups received 800 IU of vitamin D per day. During the follow-up period, BMD of the left hip and lumbar spine (as the main indicator) was measured using dual-energy X-ray absorptiometry at the baseline, 1 and 2 years. Both three BMD measures and the changes of BMD over 2 years were used to analyze. Before adjusting for covariates, BMD in group A of the lumbar spine and groups A and B of greater trochanter decreased significantly from the baseline over time but increased significantly in the rest groups of the lumbar spine and greater trochanter and in three groups of Ward's triangle. There were significant differences across the three groups for changes of BMD in the greater trochanter and Ward's triangle. When adjusting for covariates, there were significant decreases with time in group A of the spine (P = 0.001), groups A and B of greater trochanter (P = 0.0002 and P = 0.04, respectively) and increases in groups B and C of Ward's triangle (P = 0.03 and P = 0.004, respectively). BMD change in the greater trochanter was significantly different among three groups. For healthy postmenopausal women, high calcium milk powder supplementation was better in retarding bone loss than medium and low calcium in the greater trochanter. Considering the dietary calcium intake of postmenopausal women in north of China, a dose of 900 mg/day is considered as the most appropriate calcium supplementation for greater trochanter but not for other sites.
authors.affiliation: Department of Biostatistics, Public Health College, Harbin Medical University, Baojian Road 157, Harbin City, Heilongjiang Province, China.
authors.forename: Yongjie
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Biostatistics, Public Health College, Harbin Medical University, Baojian Road 157, Harbin City, Heilongjiang Province, China.
authors.forename: Yaming
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Department of Biostatistics, Public Health College, Harbin Medical University, Baojian Road 157, Harbin City, Heilongjiang Province, China.
authors.forename: Biao
authors.initials: B
authors.lastname: Xie
authors.affiliation: Medical Department, Harbin Medical University, Baojian Road 157, Harbin City, Heilongjiang Province, China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: The Healthy City Construction Guidance Center of Hangzhou City, Yanan Road 484, Hangzhou City, Zhejiang Province, China.
authors.forename: Xianfu
authors.initials: X
authors.lastname: Ma
authors.affiliation: The Center of Disease Control and Prevention of Ningbo City, Yongfeng Road 237, Hangzhou City, Zhejiang Province, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.affiliation: Department of Biostatistics, Public Health College, Harbin Medical University, Baojian Road 157, Harbin City, Heilongjiang Province, China. liumeina369@163.com.
authors.forename: Meina
authors.initials: M
authors.lastname: Liu
authors.affiliation: Department of Biostatistics, Public Health College, Harbin Medical University, Baojian Road 157, Harbin City, Heilongjiang Province, China. zqj81129@sina.com.
authors.forename: Qiuju
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000368:Aged; D000818:Animals; D015519:Bone Density / Q000187:drug effects*; D002136:Calcium, Dietary / Q000008:administration & dosage* / Q000494:pharmacology; D002681:China / Q000453:epidemiology; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008875:Middle Aged; D008892:Milk; D015663:Osteoporosis, Postmenopausal / Q000000981:diagnostic imaging / Q000178:diet therapy / Q000453:epidemiology; D017698:Postmenopause / Q000187:drug effects*; D011208:Powders; D011859:Radiography
chemical_list: D002136:Calcium, Dietary; D011208:Powders
keywords: Bone mineral density; Calcium supplementation; Osteoporosis; Postmenopausal women