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Assessment of dietary nitrate intake in humans: a systematic review

Lookup NU author(s): Abrar Babateen, Gianfranco Fornelli, Professor Lorenzo Donini, Professor John Mathers, Dr Mario Siervo



This is the authors' accepted manuscript of an article that has been published in its final definitive form by Oxford University Press, 2018.

For re-use rights please refer to the publisher's terms and conditions.


Background: 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. Objective: A systematic review was conducted to ascertain the dietary assessment methods used and to provide estimates of daily nitrate intake in humans. Design: Relevant articles were identified by a systematic search of 3 electronic databases (PubMed, Web of Science, and Embase) from inception until February 2018. 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 indexes of economic development [Gross Domestic Product (GDP) and KOF Index of Globalization]. Results: A total of 55 articles were included. Forty-two studies investigated associations between nitrate intake and disease risk; 36 (87%) of these studies examined the association between nitrate intake and cancer risk, whereas only 6 studies explored the association of nitrate intake with the 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 intakes in healthy and patient populations were 108 and 110 mg/d, respectively. We found a significant inverse correlation of nitrate intake with GDP (r = -0.46, P < 0.001) and KOF index (r = -0.31, P = 0.002). Conclusions: The median estimated daily nitrate intakes by healthy and patient populations were similar, and these values were below the safe upper intake of daily intake (3.7 mg nitrate ion/kg 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. The association between nitrate intake and risk of cardiometabolic diseases needs further investigation. The protocol for this systematic review has been registered in the PROSPERO database (; CRD number: 42017060354).

Publication metadata

Author(s): Babateen AM, Fornelli G, Donini LM, Mathers JC, Siervo M

Publication type: Article

Publication status: Published

Journal: The American Journal of Clinical Nutrition

Year: 2018

Volume: 108

Issue: 4

Pages: 878-888

Print publication date: 01/10/2018

Online publication date: 12/10/2018

Acceptance date: 27/04/2018

Date deposited: 19/02/2021

ISSN (print): 0002-9165

ISSN (electronic): 1938-3207

Publisher: Oxford University Press


DOI: 10.1093/ajcn/nqy108

PubMed id: 30321271


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Funder referenceFunder name
MR/N007921/1Medical Research Council (MRC)