Poster Topical Area: Nutritional Epidemiology
Location: Hall D
Poster Board Number: 751
Objective: The nitrate content of foods and water is highly variable which has implications for the compilation of food composition databases and assessment of dietary nitrate intake. This systematic review was conducted to ascertain the dietary assessment methods used and to provide estimates of daily nitrate intake in humans.
Method: Relevant articles were identified by a systematic search of three electronic databases (PubMed, Web of Science and Embase) from inception until November 2017. Observational studies conducted in adult populations and reporting information on dietary assessment methods and daily nitrate intake were included. Ecological analyses were conducted to explore the association of nitrate intake with Gross Domestic Product (GDP, in US dollars).
Results:54 articles were included. 42 studies investigated associations between nitrate intake and disease risk. Of these studies, 36 studies examined the association between nitrate intake and cancer risk whereas the remaining studies showed the association between nitrate intake and risk of diabetes, glaucoma, kidney failure, hypertension and atherosclerotic vascular disease. The majority of studies used food frequency questionnaires to assess nitrate intake (n=43). The median daily nitrate intake in healthy and patient populations was 109 and 110mg/day, respectively. We found a significant inverse correlation between nitrate intake and GDP (r=-0.45, p<0.001).
Conclusions: The median estimated daily nitrate intakes by healthy and patient populations were similar and these values were below the safe upper limit of daily intake (3.7 mg nitrate ion/kilogram body weight). However, there is considerable heterogeneity in the application of food composition tables which may have implications for the accuracy of estimated daily nitrate intake. Epidemiological studies are needed to investigate associations between nitrate intake and risk of cardio-metabolic diseases.
PhD candidature (BSc, MRes)
Newcastle, England, United Kingdom