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Updated: Jan 20, 2026
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Models of Bone Metastasis
Published on: September 4, 2012
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高用量ビタミンDサプリメントが体密度と骨強度に与える影響:ランダム化臨床試験
Lauren A Burt1, Emma O Billington1, Marianne S Rose2
1McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Canada.
JAMA
|August 28, 2019
まとめ
高用量ビタミンDサプリメント (毎日4000IUまたは1万IU) は,健康な成人の骨のミネラル密度 (BMD) や強度を改善しませんでした. 400 IUの1日用量と比較して,より高い用量は,放射性および小腿骨骨質量減少と関連していました.
科学分野:
- 内分泌学
- 骨の代謝
- 栄養学
背景:
- 容認できる上位摂取量以上のビタミンDの長期的効果を調査した研究はほとんどありません.
- 約3%のアメリカ人は,毎日4000IU以上のビタミンDを摂取していると報告しています.
研究 の 目的:
- ビタミンDの摂取量による骨密度 (BMD) と骨強度への影響を評価する.
主な方法:
- 55歳から70歳の 311人の健康な成人を対象とした 3年間のダブルブラインドランダム化臨床試験です.
- 参加者は毎日400 IU,4000 IU,または10,000 IUのビタミンD3を投与された.
- 骨のミネラル密度と強さは,高解像度周辺定量コンピュータトモグラフィーと有限要素解析を用いて評価された.
主要な成果:
- 400 IU群と比較して,より高いビタミンD用量 (4000 IUおよび10,000 IU) は,統計的に有意な放射線体積 BMD の低下をもたらしました.
- 400IUの投与量と比較して,10,000IUの投与量では,シビアル体積BMDが有意に低かった.
- 骨の強度 (障害負荷) に関して,半径または骨の間で有意な差異は認められなかった.
結論:
- 健康な成人の骨の健康に,毎日4000 IUまたは10,000 IUのビタミンDサプリメントは効果を示さなかった.
- 研究結果によると 大量のビタミンDは 有益ではない可能性があり 潜在的有害性については さらに調査する必要があります
- これらの結果は,この集団の骨の健康を改善するために,高用量のビタミンDを日常的に使用することを支持しません.
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