Cohort studyindependent cross-checkabstract checked★ key study I-VEG-124 standard review

Nitrate source matters

Source-specific nitrate intake and all-cause mortality in the Danish Diet, Cancer, and Health Study.

Overview

Bondonno NP et al.. Eur J Epidemiol 2024 · PMID 38802612 · DOI 10.1007/s10654-024-01133-5

Nitrate from plants was linked to 17% lower mortality, whereas nitrate from processed meat and tap water was linked to higher mortality.

Does the study support the specific claim? No · Methodological quality: moderate

Study explained simply

What did the researchers want to find out?: Compare nitrate sources and mortality.
How was the study done?: Cohort, 27 years.
How many people, animals or samples were studied?: 52,247 adults.
What was actually found?: Plant nitrate inverse; meat/water nitrate positive.
How large was the observed effect?: HR 0.83 (0.80-0.87) plant.
What do the results mean in everyday life?: Nitrate in vegetables is not the nitrate to worry about.
What are the study's limitations?: Observational.
What does it say about Elawady's specific claim?: Contradicts the claim.
Do the results apply to Germany and Europe?: European.
What can explicitly not be concluded from this study?: Cannot prove causation.

Authors: Bondonno NP et al.
Journal: Eur J Epidemiol
Year: 2024
Identifier: PMID 38802612 DOI 10.1007/s10654-024-01133-5
Verification: verified – PubMed efetch 2026-10-26; Crossref 2026-10-26
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: COI statement: The authors have no relevant financial or non-financial interests to disclose.

Do associations of nitrate/nitrite with mortality depend on dietary source?

Study design: Cohort study – Prospective cohort (Danish Diet, Cancer and Health), 27 years, source-specific nitrate/nitrite
Population: Danish adults
Country: Denmark
Period: 27 years follow-up
Sample size: 52,247
Inclusion and exclusion criteria: not stated in abstract

Exposure / intervention: Plant-sourced, natural animal-sourced, additive-permitted meat-sourced and tap-water nitrate/nitrite
Comparator: Q1
Endpoints: All-cause, CVD and cancer mortality
Statistical methods: Restricted cubic splines in Cox models; stratification by NOC-formation modifiers

Results: Plant-sourced nitrate Q5 vs Q1: HR 0.83 (0.80-0.87) all-cause mortality; natural animal-sourced 1.09 (1.04-1.14); additive-permitted meat-sourced 1.19 (1.14-1.25); tap-water 1.19 (1.14-1.25). Similar for nitrite and for CVD and cancer mortality with some exceptions.
Absolute risks: not reported
Authors' conclusion: Nitrate/nitrite from plant sources are inversely associated, and those from animal, processed-meat and tap-water sources positively associated, with mortality.

CIs log-symmetric within rounding (stats/C-VEG-08_nitrate.py).

Separates vegetable nitrate (inverse association) from processed-meat and water nitrate (positive association).

Ward 2010.

European.

Strong evidence against the claim that vegetable nitrate harms adults; processed meat is the relevant nitrate concern.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	moderate
Risk of bias	some concerns
Precision of results	high
Directness	direct
Reproducibility	partly replicated
Consistency with the overall evidence	consistent
Regional transferability	high
Adequacy of the interpretation (by the archive)	not applicable

Mechanisms.