Although nitrates and nitrites have been approved for use as food preservatives and curing agents in meat products for decades, their health implications remain a subject of intense debate. Recently the International Agency for Research on Cancer of the World Health Organization has classified nitrate/nitrite-treated processed meats as Group 1 carcinogenic to humans. However, as processed meats account for only a minor portion of the total human nitrates/nitrites exposure, other factors are more likely responsible for the increased cancer risk observed in the subjects of a number of epidemiological studies. Also, nitrates and nitrites can serve both as the precursors and end products of nitric oxide, an important endogenous signal molecule. By helping in maintaining nitric oxide homeostasis, nitrates and nitrites may provide potential benefits beyond their need as food preservatives, and clinical trials for possible medical uses of nitrites and nitrates are in progress. Thus, a reassessment of the health implications of nitrites and nitrates is appropriate and needed.