Effects of milk powder intervention on bone mineral density and indicators related to bone metabolism in Chinese adolescents

Abstract

SummaryThe study is to determine the effects of milk powder on bone density and metabolism in healthy adolescents. Vitamin D and calcium supplements increased IGF-1 but did not affect bone mineralization or turnover. Higher vitamin D in combination with sufficient calcium supplementation in such populations requires attention.IntroductionBoth calcium and vitamin D play an important role in bone mineralization in adolescents.MethodsIn this one and a half-year randomized controlled trial, 232 participants (aged 12–15 years) were randomly assigned to three intervention groups receiving milk powder fortified with vitamin D 400 IU plus calcium 300, or 600, or 900 mg [Ca3D (n = 54), Ca6D (n = 56), and Ca9D (n = 49)], or one control group maintaining habitual diet [control (n = 73)]. Bone turnover markers, serum intact PTH, 25(OH)D, and IGF-1 levels were measured at baseline and one and a half years, and bone mineral contents and bone areal mineral density were measured by Dual-energy X-ray absorptiometry (DXA) at baseline, one year, and one and a half years.ResultsBaseline average serum 25(OH)D level and calcium intake were 29.4 nmol/L and 363.5 mg/day, respectively. There was a significant increase in bone turnover, total body, hip, lumbar spine bone mineral density (BMD), and total body BMC as well as slight fluctuations in 25(OH)D levels over one and a half years without between-group differences. Significantly decreased serum PTH level was only observed in the Ca6D group (31%, p < 0.0001), in which the intervention effect was also significant (p = 0.0029) compared with the control group. IGF-1 levels increased significantly in all intervention groups (18.5 to 22.8%, p < 0.05) but decreased in the control group (16.5%, p < 0.05), and the group by time interaction was also significant (p = 0.0029).ConclusionsOur study showed that in healthy adolescents with low vitamin D status and calcium intake, mild vitamin D and mild to modest calcium supplements increased IGF-1 but did not affect bone mineralization or turnover. Higher vitamin D in combination with sufficient calcium supplementation in such populations requires attention.

The Effects of Vitamin D Fortified Products on Bone Bi-omarkers: A Systematic Review and Meta-Analysis

“…Participants in seventeen studies were only females ( 5 , 18 – 33 ) and in two studies were only males ( 34 , 35 ). Eight studies addressed children and adolescents ( 36 – 43 ). The mean age of subjects varied from 2 yr ( 42 ) to 84 years ( 18 ).…”

“…are different from the other studies. These two studies were in children (< 15-year-old) ( 37 , 43 ), while the other studies were in participants older than 50-year-old. Sensitivity analysis indicated that by omitting these studies the pooled estimate was still in favor of intervention (Difference in means=9.38, P -value=0.008, CI 95%: 2.48 to 16.29).…”

The effect of calcium supplementation in people under 35 years old: A systematic review and meta-analysis of randomized controlled trials

“…9-12 22-60 Table 1 shows the baseline characteristics of the included studies. Of the 43 RCTs, 20 used dietary sources of calcium, 11 12 22 23 25 27-29 40 43-46 48 49 53 54 56 60 and 23 used calcium supplements (including calcium, calcium citrate malate and calcium phosphate). 9 10 24 26 30-39 41 42 47 50-52 55 57 59 The median baseline dietary calcium intake was 714 mg/day; the duration of calcium supplementation intervention did not exceed 2 years in most trials (38/43); and the dose of calcium intervention did not exceed 1000 mg/day in most trials (38/43).…”

“…9 10 However, several clinical trials have concluded that calcium supplementation may not be associated with calculated bone mass or strength. 11 12 Narrative reviews have also concluded that calcium supplementation may have small nonprogressive effects on BMD or BMC. 13 14 To summarize the studies above, there have been considerable debates about whether calcium supplementation has effects on bone health among young people.…”

The effect of calcium supplementation in people under 35 years old: A systematic review and meta-analysis of randomized controlled trials

“…Several clinical trials have shown positive effects of calcium supplementation on BMD or BMC in children ( Lloyd et al, 1993 ; Khadilkar et al, 2012 ). However, several clinical trials have concluded that calcium supplementation may not be associated with calculated bone mass or strength ( Lu et al, 2019 ; Vogel et al, 2017 ). Narrative reviews have also concluded that calcium supplementation may have small nonprogressive effects on BMD or BMC ( Winzenberg et al, 2006 ; Huncharek et al, 2008 ).…”