From an epidemiological perspective, nitrates are commonly thought to be adverse to health due to a long-standing restriction on how much nitrate can be in drinking water (50mg/L) or ground water (due to accumulating in vegetables) due to the risk of infantile methemoglobinemia (baby blue syndrome)[1][2] which does appear to apply to vegetables.[3][4] More commonly, the association between processed meat products that are pink in color (which very commonly use sodium nitrate as a preservative) and cancer occurrence also paints nitrates in the same negative light.[5] Conversely, vegetables are commonly stated to not be associated with cancer risk (which then raises concern about whether or not they are the same molecules).
Both consumption of vegetables (most commonly researched is beetroot[6]) and consumption of the sodium nitrate preservative cause increases in serum nitrate and nitrite, and are considered bioequivalent. In some studies that assess nitrate's bioactivity, liquid solutions of sodium nitrate are even used.[7][8][7]
There are still differences between eating processed meat and vegetables in this regard (intake of sodium through the preservative sodium nitrate and higher intake of potassium via vegetables; less conversion of nitrate into nitrosamines with coingested antioxidants) but the molecule itself is the same.
References
- ^Survey of Literature Relating to Infant Methemoglobinemia Due to Nitrate-Contaminated Water
- ^Cyanosis in Infants Caused by Nitrates in Well Water
- ^McKnight GM, Duncan CW, Leifert C, Golden MHDietary nitrate in man: friend or foeBr J Nutr.(1999 May)
- ^Chan TYVegetable-borne nitrate and nitrite and the risk of methaemoglobinaemiaToxicol Lett.(2011 Jan 15)
- ^Meat consumption and mortality - results from the European Prospective Investigation into Cancer and Nutrition
- ^Wylie LJ, Kelly J, Bailey SJ, Blackwell JR, Skiba PF, Winyard PG, Jeukendrup AE, Vanhatalo A, Jones AMBeetroot juice and exercise: pharmacodynamic and dose-response relationshipsJ Appl Physiol.(2013 May 2)
- ^Larsen FJ, Weitzberg E, Lundberg JO, Ekblom BDietary nitrate reduces maximal oxygen consumption while maintaining work performance in maximal exerciseFree Radic Biol Med.(2010 Jan 15)
- ^Sindler AL, Fleenor BS, Calvert JW, Marshall KD, Zigler ML, Lefer DJ, Seals DRNitrite supplementation reverses vascular endothelial dysfunction and large elastic artery stiffness with agingAging Cell.(2011 Jun)