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reactive oxygen (i.e. free radicals, which can be destructive at high concentrations)
活性酸素は体を傷つける。
Reactive oxygen can damage the body.
激しい運動で活性酸素が増えると言われる。
Intense exercise is said to increase reactive oxygen.
野菜には活性酸素の害を抑える抗酸化成分が豊富だ。
Vegetables are rich in antioxidants that suppress the harmful effects of reactive oxygen.