title: Carotenoids and cardiovascular disease: what research gaps remain?
abstract: OBJECTIVE
  Dietary and blood carotenoids, including alpha-carotene, beta-carotene, lycopene, lutein/zeaxanthin, and beta-cryptoxanthin, have been examined in a number of epidemiological studies in recent years for the risk of cardiovascular disease. This review assimilated the existing and recent literature on carotenoids and cardiovascular disease and considered what research gaps may remain.
  
  
  RESULTS
  Numerous large cohort studies have been published in largely American men and women that have examined dietary intake or blood levels of total or individual carotenoids with the risk of various cardiovascular endpoints. Overall, early, promising results have grown increasingly inconsistent over time. More recently, studies examining lycopene and lutein/zeaxanthin have offered more promising data on a possible, but not yet established, inverse association with the risk of cardiovascular disease. Recent epidemiological data on beta-cryptoxanthin and cardiovascular disease are lacking. Primary and secondary prevention trials have extensively examined beta-carotene, but not other carotenoids, for the risk of cardiovascular disease as either the primary or secondary endpoint with largely null results. More recent studies have focused on individual carotenoids in relation to cardiovascular disease and require a more careful evaluation of potential mechanisms of effect.
  
  
  CONCLUSIONS
  The promise of early epidemiological studies on carotenoids and cardiovascular disease paved the way to largely disappointing results from several large prevention trials of beta-carotene. Emerging recent evidence of potential cardioprotective effects for lycopene and other carotenoids besides beta-carotene in the diet and blood suggest that there is more to be learned in the story of carotenoids and both atherosclerotic progression and clinically manifested cardiovascular disease.
authors.affiliation: Department of Medicine, Brigham & Women's Hospital and Harvard Medical School and Massachusetts Veterans Epidemiology Research and Information Center, VA Boston Healthcare System, Boston, Massachusetts 02215-1204, USA. hsesso@hsph.harvard.edu
authors.forename: Howard D
authors.initials: HD
authors.lastname: Sesso
mesh_terms: D050197:Atherosclerosis / Q000097:blood / Q000453:epidemiology / Q000517:prevention & control*; D002316:Cardiotonic Agents / Q000097:blood / Q000627:therapeutic use; D002338:Carotenoids / Q000097:blood / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D012307:Risk Factors
chemical_list: D002316:Cardiotonic Agents; D002338:Carotenoids