The contents of protein, saccharides, ascorbic acid, and electrical potential, oxidation-reduction equivalent in 24 kinds of fresh vegetables and fruits were reported. The linear regression and correlation analysis were used to assess the relationship between health protection (nitrite eliminatin and antioxidation) and the nutrition characteristics of the materials. In a model system of simulated stomach condition, nitrite, one of the substrates for the formation of N-nitroso compounds, was efficiently eliminated by the active constituents of fresh vegetables and fruits. The correlation coefficient between the amount of eliminated nitrite and the antioxidative activity (inhibition rate of the formation of thiobarbituric acid-reactive substance) was 0.5115 (p0.05) , respectively. It was shown that the synthetic oxidation-reduction characteristic of nutrition constituents in fresh vegetables and fruits may be the natural cause of long life and health protection.