Nitrate and vitamin C from fruits and vegetables: Impact of intake variations on nitrate and nitrite excretions of humans
The objective of the study was to determine nitrate + nitrite excretions of human subjects fed variable amounts of nitrates and nitrites and vitamin C from fruits and vegetables. During four, randomly-arranged experimental periods of seven days each, the 12 apparently healthy, adult human subjects consumed laboratory controlled, constant, diets which were systematically varied in kinds of fruits and vegetable to provide the four following variations: 414 mg nitrate + nitrite and 23 mg vitamin C, 412 mg nitrate + nitrite and 177 mg vitamin C, 23 mg nitrate + nitrite and 39 mg vitamin C, and 21 mg nitrate + nitrite and 193 mg vitamin C per subject per day, respectively. Subjects made complete collections of urine and stools throughout the study. Regardless of type of experimental diet fed, no nitrates and nitrites were detected in the feces. Urinary excretion of nitrate + nitrite was significantly greater at the higher levels of nitrate + nitrite intake than at the lower intake levels. Increased intake of vitamin C at either level of nitrate + nitrite intake resulted in apparent decreased urinary excretions of nitrite + nitrate.
Key wordsNitrate Nitrite Ascorbic acid
Unable to display preview. Download preview PDF.
- Anderson K, Valceschini G, Kies C (1982) Nitrate and nitrite excretion of humans as influenced by addition of spinach to free-choice diets. Nutr Rep Int 27: 77–85.Google Scholar
- Comly HH (1945) Cyanosis in infants caused by nitrates in well water. JAMA 129: 112–116.Google Scholar
- Fine DH (1982) Nitrosamines in the general environment and food, in PN Magee (ed) Nitrosamines and Human Cancer. Harbor Press, Cold Spring Harbor, NY, pp. 199, 201.Google Scholar
- Forman D (1987) Gastric cancer, diet and nitrate exposure. Br Med J 294: 528–529.Google Scholar
- Gray JE, Dugan LR (1975) Inhibition of N-nitrosamine formation in model food systems. J Food Sci 40: 981–984.Google Scholar
- Hartman PE (1982) Overview: nitrite load in the upper gastrointestinal tract — past, present, and future. in: PN Magee (ed.) Nitrosamines and Human Cancer. Harbor Press, Cold Spring Harbor, NY, p. 416.Google Scholar
- Lee K, Greger JL, Consaul JR, Graham KL, Chinn BL (1986) Nitrate, nitrite balance and de novo synthesis of nitrate in humans consuming cured meats. Am J Clin Nutr 44: 1188–1194.Google Scholar
- Lu SH, Ohshima H, Fu HM, Tran Y, Li FM, Blettner M, Wahrendorf J, Bartsch H (1986) Urinary excretion of N-nitrosamino acids and nitrate by inhabitants of high- and low-risk areas for esophageal cancer in northern China: endogenous formation of nitrosoproline and its inhibition by vitamin C. Cancer Res 46: 1485–1491.PubMedGoogle Scholar
- Mirvish SS (1983) The etiology of gastric cancer: intragastric nitrosamide formation and other theories. J Natl Cancer Inst 71: 630–647.Google Scholar
- National Research Council/National Academy of Science (1981) The Health Effects of Nitrate, Nitrite and N-nitroso Compounds, I. National Academy of Science, Washington, DC.Google Scholar