Estimated dietary intakes of nitrates in vegetarians compared to a traditional diet in Poland and acceptable daily intakes: is there a risk?

BACKGROUND Vegetarian diets, by definition, are rich in vegetables and so may have high levels of nitrates, that can elicit both positive or negative effects on the human body. Exposure to nitrates can thus be potentially higher for this population group. OBJECTIVE To estimate dietary nitrates intakes in Polish vegetarians and compare these with the Polish average. MATERIAL AND METHODS A sample of 86 vegetarians were surveyed via a questionnaire to determine nitrate intake for those adopting a vegetarian diet. Nitrate intakes for the average Pole were obtained from the Central Statistical Office. RESULTS The domestic intake of nitrate, per average person, during 2000-2009, ranged from 115.5 to 133.7 mg NaNO3 with a mean of 125 mg NaNO3 of which 35.4% constituted the Acceptable Daily Intake (ADI). For vegetarians, the corresponding levels ranged from 37.3 to 2054.3 mg NaNO3 with a mean intake of 340.1 mg NaNO3 of which 95.8% represented the ADI. This was almost twice more than values obtained from calculating nitrate intakes of a typical 7-day vegetarian menu; 104.5 to 277.6 mg NaNO3, with a mean 175.9 mg NaNO3 with the 49.1% making up the ADI. CONCLUSIONS The nitrate intakes in the tested vegetarians were 140 to 270% higher than ones for the average Pole, however in both cases the ADI was not exceeded. Nevertheless, the higher intake of nitrates so observed in vegetarians can be hazardous to some from this population group.