Dietary and circulating vitamin C, vitamin E, β-carotene and risk of total cardiovascular mortality: a systematic review and dose-response meta-analysis of prospective observational studies

Public Health Nutr. 2019 Jul;22(10):1872-1887. doi: 10.1017/S1368980018003725. Epub 2019 Jan 11.

Abstract

Objective: The present review aimed to quantify the association of dietary intake and circulating concentration of major dietary antioxidants with risk of total CVD mortality.

Design: Systematic review and meta-analysis.

Setting: Systematic search in PubMed and Scopus, up to October 2017.ParticipantsProspective observational studies reporting risk estimates of CVD mortality across three or more categories of dietary intakes and/or circulating concentrations of vitamin C, vitamin E and β-carotene were included. A random-effects meta-analysis was conducted.

Results: A total of fifteen prospective cohort studies and three prospective evaluations within interventional studies (320 548 participants and 16 974 cases) were analysed. The relative risks of CVD mortality for the highest v. the lowest category of antioxidant intakes were as follows: vitamin C, 0·79 (95 % CI 0·68, 0·89; I 2=46 %, n 10); vitamin E, 0·91 (95 % CI 0·79, 1·03; I 2=51 %, n 8); β-carotene, 0·89 (95 % CI 0·73, 1·05; I 2=34 %, n 4). The relative risks for circulating concentrations were: vitamin C, 0·60 (95 % CI 0·42, 0·78; I 2=65 %, n 6); α-tocopherol, 0·82 (95 % CI 0·76, 0·88; I 2=0 %, n 5); β-carotene, 0·68 (95 % CI 0·52, 0·83; I 2=50 %, n 6). Dose-response meta-analyses demonstrated that the circulating biomarkers of antioxidants were more strongly associated with risk of CVD mortality than dietary intakes.

Conclusions: The present meta-analysis demonstrates that higher vitamin C intake and higher circulating concentrations of vitamin C, vitamin E and β-carotene are associated with a lower risk of CVD mortality.

Keywords: Antioxidants; CVD; Meta-analysis; Observational studies.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antioxidants / analysis
  • Ascorbic Acid / analysis*
  • Biomarkers / blood
  • Cardiovascular Diseases / etiology
  • Cardiovascular Diseases / mortality*
  • Diet / adverse effects*
  • Eating
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nutritional Status
  • Observational Studies as Topic
  • Prospective Studies
  • Risk
  • Risk Factors
  • Vitamin E / analysis*
  • beta Carotene / analysis*

Substances

  • Antioxidants
  • Biomarkers
  • beta Carotene
  • Vitamin E
  • Ascorbic Acid