title: Effect of dietary lutein and zeaxanthin on plasma carotenoids and their transport in lipoproteins in age-related macular degeneration.
abstract: BACKGROUND
  Low dietary intakes and low plasma concentrations of lutein and zeaxanthin are associated with an increased risk of age-related macular degeneration (AMD). No studies have challenged AMD patients with a diet high in lutein and zeaxanthin.
  
  
  OBJECTIVE
  The objective was to examine the effect of diets low or high in lutein and zeaxanthin on plasma carotenoids and their transport in AMD patients.
  
  
  METHODS
  Seven AMD patients and 5 control subjects were fed a low-lutein, low-zeaxanthin diet ( approximately 1.1 mg/d) for 2 wk, which was followed by a high-lutein, high-zeaxanthin diet ( approximately 11 mg/d) for 4 wk. Ten subjects continued the diet for 8 wk. Plasma and lipoprotein carotenoids were measured by HPLC.
  
  
  RESULTS
  The high-lutein, high-zeaxanthin diet resulted in 2- to 3-fold increases in plasma concentrations of lutein and zeaxanthin and other carotenoids, except lycopene, in the AMD patients and the control subjects. With this diet, 52% of the lutein and 44% of the zeaxanthin were transported by HDL; approximately 22% of lutein and zeaxanthin was transported by LDL. Only 20-25% of alpha-carotene, beta-carotene, and lycopene was transported by HDL; 50-57% was transported by LDL.
  
  
  CONCLUSIONS
  The AMD patients and control subjects responded similarly to a diet high in lutein and zeaxanthin; plasma carotenoid concentrations increased greatly in both groups, and the transport of carotenoids by lipoproteins was not significantly different between the groups. This finding suggests that abnormalities in the metabolism of lutein and zeaxanthin in AMD may reside in the uptake of lutein and zeaxanthin from the plasma and transport into the retina.
authors.affiliation: Department of Medicine, Oregon Health and Science University, Portland, OR 97239-3098, USA. wangwe@ohsu.edu
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Sonja L
authors.initials: SL
authors.lastname: Connor
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Johnson
authors.forename: Michael L
authors.initials: ML
authors.lastname: Klein
authors.forename: Shannon
authors.initials: S
authors.lastname: Hughes
authors.forename: William E
authors.initials: WE
authors.lastname: Connor
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001692:Biological Transport; D001835:Body Weight; D002338:Carotenoids / Q000097:blood*; D004032:Diet; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood; D008074:Lipoproteins / Q000097:blood*; D014975:Lutein / Q000097:blood / Q000494:pharmacology*; D008268:Macular Degeneration / Q000097:blood* / Q000178:diet therapy; D008297:Male; D024341:Xanthophylls / Q000097:blood / Q000494:pharmacology*; D065146:Zeaxanthins
chemical_list: D008055:Lipids; D008074:Lipoproteins; D024341:Xanthophylls; D065146:Zeaxanthins; D002338:Carotenoids; D014975:Lutein