The apparent inverse association between dietary carotene intake and risk of cardiovascular mortality disappeared after adjustment for other cardioprotective dietary intakes: The Japan collaborative cohort study

Nutr Metab Cardiovasc Dis. 2021 Oct 28;31(11):3064-3075. doi: 10.1016/j.numecd.2021.07.026. Epub 2021 Jul 30.

Abstract

Background and purpose: An effect of dietary carotenes on risk of cardiovascular disease (CVD) is uncertain. We aimed to investigate whether the association between dietary carotenes intake and risk of CVD mortality will persist after controlling for the intakes of potential cardioprotective dietary factors that correlate with dietary alpha- and/or beta-carotenes.

Methods and results: We followed up a total of 58,646 Japanese between 1988 and 1990 and 2009. We used a food frequency questionnaire (FFQ) to determine the dietary intakes of carotenes, and estimated the hazard ratios (HRs) and 95% confidence intervals (CIs) of CVD mortality in relation to carotene intake by the proportional hazard regression developed by David Cox. During 965,970 person-years of follow-up (median 19.3 years), we identified 3388 total CVD deaths. After adjusting for demographic and lifestyle factors, dietary intakes of alpha-carotene were significantly associated with the reduced risk of mortality from coronary heart disease (CHD); adjusted HR (95% CI) in the highest versus lowest quintiles of intake was 0.75 (0.58-0.96; P-trend = 0.02) and dietary intakes of beta-carotene were significantly associated with the reduced risk of mortality from CVD, CHD, and other CVD; adjusted HRs (95% CIs) were 0.88 (0.79-0.98; P-trend = 0.04), 0.78 (0.61-0.99; P-trend = 0.01), and 0.81 (0.67-0.98; P-trend = 0.04), respectively. However, after further adjusting for the dietary intakes of potassium, calcium, vitamins C, E, or K, these associations disappeared.

Conclusions: -Dietary alpha- and beta-carotene intakes were not associated with risk of CVD mortality after controlling for intakes of other potential cardioprotective nutrients.

Keywords: Alpha-carotene; Beta-carotene; Cardiovascular mortality; Follow-up study; Japan; Potassium.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cardiovascular Diseases / diagnosis
  • Cardiovascular Diseases / mortality
  • Cardiovascular Diseases / prevention & control*
  • Carotenoids / administration & dosage*
  • Cause of Death
  • Diet, Healthy*
  • Female
  • Humans
  • Japan / epidemiology
  • Male
  • Middle Aged
  • Nutritive Value
  • Prognosis
  • Prospective Studies
  • Protective Factors
  • Risk Assessment
  • Risk Factors
  • Risk Reduction Behavior*
  • Time Factors
  • beta Carotene / administration & dosage*

Substances

  • beta Carotene
  • Carotenoids
  • alpha-carotene