(c)flickr & Chiot’s Run
大量のビタミンCの摂取で血圧が低下するようだ。ジョンズ・ホプキンズ大学の研究者らが，ビタミンCとプラセボの血圧低下作用を比較した無作為化対照試験29件を分析した結果，１日の推奨摂取量の約5倍，500 mgの摂取が短期間で血圧を3.84 mmHg低下させていた。高血圧患者に限定すると，5 mmHgの低下だった。この効果は一般に降圧薬を使った場合の約10 mmHgと比べると小さいが，米国全体で1人当たり3 mmHg低下すれば，脳卒中が顕著に減るという。ただし，研究者らは，治療目的のサプリメントの使用は研究がさらに進むまで推奨できないとしている。（吉田素子）
Big Doses of Vitamin C May Lower Blood Pressure
But Hold the Supplements, for Now, Researchers Say
Taking large doses of vitamin C may moderately reduce blood pressure, according to an analysis of years of research by Johns Hopkins scientists. But the researchers stopped short of suggesting people load up on supplements.
“Our research suggests a modest blood pressure lowering effect with vitamin C supplementation, but before we can recommend supplements as a treatment for high blood pressure, we really need more research to understand the implications of taking them,” says Edgar “Pete” R. Miller III, MD, PhD, an associate professor in the division of general internal medicine at the Johns Hopkins University School of Medicine and leader of the study published in The American Journal of Clinical Nutrition.
Roughly 30 percent of adults in the United States have high blood pressure, or hypertension, an important risk factor for heart disease and stroke. Successful treatment may include drugs, exercise, weight loss, and dietary changes such as reducing salt intake. Some experts believe that large amounts of vitamin C, an essential micronutrient found primarily in fruits and vegetables, could lower pressure as well, but randomized, controlled dietary intervention studies -- the gold standard of nutrition research -- have produced mixed results.
Miller and his colleagues reviewed and analyzed data from 29 randomized, controlled, previously published clinical trials that reported systolic and/or diastolic blood pressure values and also compared vitamin C intake to a placebo.
［単語和訳］
Doses：用量 Vitamin C：ビタミンC Blood Pressure：血圧 Supplements：栄養補助食品，サプリメント Researchers：研究者
moderately：中程度に according to：～によると stopped short of：～するまでには至らなかった load up on：～を大量に飲む
supplementation：補給 implications：影響 MD：医師 PhD：博士 associate professor：准教授 general internal medicine：一般内科 Clinical Nutrition：臨床栄養学 （The American Journal of Clinical Nutrition は雑誌名）
hypertension：高血圧 risk factor：危険因子 heart disease：心疾患 stroke：脳卒中 dietary：食事の intake：摂取 micronutrient：微量栄養素 primarily：主に randomized：無作為化 controlled：対照群を設定した intervention：（治療）介入 gold standard：究極の判断基準
colleagues：同僚（研究仲間） clinical trials：臨床試験 systolic and/or diastolic blood pressure：収縮期および／または拡張期血圧 placebo：プラセボ
