Food sources of nitrates and nitrites: the physiologic context for potential health benefits

Abstract

The presence of nitrates and nitrites in food is associated with an increased risk of gastrointestinal cancer and, in infants, methemoglobinemia. Despite the physiologic roles for nitrate and nitrite in vascular and immune function, consideration of food sources of nitrates and nitrites as healthful dietary components has received little attention. Approximately 80% of dietary nitrates are derived from vegetable consumption; sources of nitrites include vegetables, fruit, and processed meats. Nitrites are produced endogenously through the oxidation of nitric oxide and through a reduction of nitrate by commensal bacteria in the mouth and gastrointestinal tract. As such, the dietary provision of nitrates and nitrites from vegetables and fruit may contribute to the blood pressure-lowering effects of the Dietary Approaches to Stop Hypertension (DASH) diet. We quantified nitrate and nitrite concentrations by HPLC in a convenience sample of foods. Incorporating these values into 2 hypothetical dietary patterns that emphasize high-nitrate or low-nitrate vegetable and fruit choices based on the DASH diet, we found that nitrate concentrations in these 2 patterns vary from 174 to 1222 mg. The hypothetical high-nitrate DASH diet pattern exceeds the World Health Organization's Acceptable Daily Intake for nitrate by 550% for a 60-kg adult. These data call into question the rationale for recommendations to limit nitrate and nitrite consumption from plant foods; a comprehensive reevaluation of the health effects of food sources of nitrates and nitrites is appropriate. The strength of the evidence linking the consumption of nitrate- and nitrite-containing plant foods to beneficial health effects supports the consideration of these compounds as nutrients.

Improvement in blood pressure after short-term inorganic nitrate supplementation is attenuated in cigarette smokers compared to non-smoking controls

“…These findings are consistent with the emerging body of evidence to support improved vascular health following dietary NO 3 -supplementation (4-16 mmol·day -1 ) in younger [11][12][13] and older [16,17] normotensive adults, and in individuals with hypertension [18], peripheral artery disease [19] and heart failure [20]. Therefore, enriching the diet with NO 3 -, at a dose that can be readily achieved by a diet high in vegetables [4,7,9], might represent a practical and cost-effective intervention to lower cardiovascular disease morbidity and mortality.…”

“…It has been suggested that the cardio-protective effects of diets rich in fruit and vegetables might be linked to their high inorganic nitrate (NO 3 -) content [7][8][9]. Vegetable consumption accounts for 60-80% of dietary NO 3 -intake [10] with leafy-green vegetables (e.g., spinach and lettuce varieties) and beetroot being particularly rich in NO 3 - [7].…”

“…Vegetable consumption accounts for 60-80% of dietary NO 3 -intake [10] with leafy-green vegetables (e.g., spinach and lettuce varieties) and beetroot being particularly rich in NO 3 - [7]. It has been reported that consuming 5 portions of NO 3 --rich vegetables for 7 days, which provided a daily NO 3 -intake of ~ 317 mg (5.1 mmol), lowered systolic blood pressure, whereas a control diet where participants avoided NO 3 --rich vegetables, resulting in a daily NO 3 -intake of ~ 8 mg (0.1 mmol), did not [9].…”

Construction of effective disposable biosensors for point of care testing of nitrite

“…Therefore, human exposure to nitrite/nitrate comes mainly from the intake of processed food like cured meats, fishes and cheeses that are treated with nitrate salts (E251, E252) and nitrite salts (E249, E250) for preservation and/or organoleptic purposes. According to the EFSA recommendations (2006/52/EC), the amounts of nitrite/nitrate added 3 to several foodstuffs should be controlled, not exceeding 150 mg kg -1 of nitrite in the case of meat product [1,6,7].…”

The detoxication of nitrate by two antioxidants or a probiotic, and the effects on blood and seminal plasma profiles and reproductive function of New Zealand White rabbit bucks

“…They showed that nitrate concentration at 600 to 700 ppm had a deleterious effect on rabbits' performance, but no attention was given to semen quality and litter traits. The adverse effect of nitrate was obvious with increasing nitrate intake in animals and humans (Shehata, 2005;DjekounBensoltane et al, 2007;Hord et al, 2009). Nitrate pollution -E-mail: attia0103753095@gmail.com could be increased because of agro-industry (Wahaab and Badawy, 2004;Burow et al, 2010).…”