{"claimId":"clm_ec_b7-vitc-heart","version":1,"status":"current","verdict":"Vitamin C for heart health: Grade C at low certainty. Systematic review: overall there is limited evidence that vitamin C supplementation improves cardiovascular biomarkers in the general population. Subgroups — people with low baseline vitamin C status or higher cardiovascular risk — may be more responsive, but this is a tentative, subgroup-level signal.","direction":"benefit","magnitude":{"metric":"other","value":null,"unit":"","ci95":null,"humanReadable":"Systematic review: overall there is limited evidence that vitamin C supplementation improves cardiovascular biomarkers in the general population. Subgroups — people with low baseline vitamin C status or higher cardiovascular risk — may be more responsive, but this is a tentative, subgroup-level signal.","baselineAbsoluteRisk":null},"certainty":"low","clinicalMeaning":"small_but_potentially_useful","applicability":{"appliesTo":["adults (subgroup signal in low-status / higher-risk)"],"doesNotApply":["children"],"unknown":["pregnancy"]},"safetyQualifiers":[],"evidenceBundleId":"eb_ec_b7-vitc-heart","citations":[{"pmid":"30683434","design":"peer-reviewed"}],"reviewedBy":{"name":"Substrate editorial","credential":"Independent research collective"},"reviewedAt":"2026-07-16T16:23:44.693Z","dateModified":"2026-07-16T16:23:44.693Z","methodologyVersion":"v1","methodologyDoi":"https://doi.org/10.5281/zenodo.21364236","canonicalUrl":"https://evidencebased.info/interventions/vitamin-c/heart-health","attribution":"Substrate (evidencebased.info), claim clm_ec_b7-vitc-heart v1, reviewed 2026-07-16","license":"CC-BY-4.0 — attribution with link required"}