title: Skin and plasma carotenoid response to a provided intervention diet high in vegetables and fruit: uptake and depletion kinetics.
abstract: BACKGROUND
  Objective biomarkers are needed to assess adherence to vegetable and fruit intervention trials. Blood carotenoids are considered the best biomarker of vegetable and fruit intake, but collecting blood is invasive and the analyses are relatively expensive for population studies. Resonance Raman spectroscopy (RRS) is an innovative method for assessing carotenoids in skin noninvasively.
  
  
  OBJECTIVE
  Our objective was to compare blood carotenoid concentrations with skin carotenoid assessments by RRS during a controlled feeding intervention.
  
  
  METHODS
  Twenty-nine participants consumed low-carotenoid diets (6 wk, phases 1 and 3), a provided diet containing 6-cup equivalents (1046 g/d) of vegetables and fruit (8 wk, phase 2), and usual diet (final 8 wk, phase 4).
  
  
  RESULTS
  At baseline, skin and plasma total carotenoid values were correlated (r = 0.61, P < 0.001). Skin and plasma carotenoid values decreased (P < 0.001) 36% and 30%, respectively, from baseline to the end of phase 1 and then increased (P < 0.001) by >200% at the end of phase 2. Plasma carotenoids returned to baseline concentrations by the middle of phase 3 and skin carotenoid concentrations by the middle of phase 4. Skin carotenoid status predicted plasma values by using a mixed linear model including all time points (r = 0.72, P < 0.001), which indicates that changes in skin carotenoid status closely follow changes in plasma across a broad range of intakes. At the individual level, skin carotenoids predicted plasma values (r = 0.70, P < 0.001) over all time points.
  
  
  CONCLUSIONS
  Skin carotenoid status assessed by resonance Raman spectroscopy is a noninvasive, objective biomarker of changes in vegetable and fruit intake.
authors.affiliation: From the USDA/Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, ND (LJ, LDW, and MJP); the University of North Dakota, Grand Forks, ND (LKJ); the Yale School of Public Health and Yale Cancer Center, New Haven, CT (STM and BC); and the Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (IVE and WG).
authors.forename: Lisa
authors.initials: L
authors.lastname: Jahns
authors.affiliation: From the USDA/Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, ND (LJ, LDW, and MJP); the University of North Dakota, Grand Forks, ND (LKJ); the Yale School of Public Health and Yale Cancer Center, New Haven, CT (STM and BC); and the Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (IVE and WG).
authors.forename: LuAnn K
authors.initials: LK
authors.lastname: Johnson
authors.affiliation: From the USDA/Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, ND (LJ, LDW, and MJP); the University of North Dakota, Grand Forks, ND (LKJ); the Yale School of Public Health and Yale Cancer Center, New Haven, CT (STM and BC); and the Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (IVE and WG).
authors.forename: Susan T
authors.initials: ST
authors.lastname: Mayne
authors.affiliation: From the USDA/Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, ND (LJ, LDW, and MJP); the University of North Dakota, Grand Forks, ND (LKJ); the Yale School of Public Health and Yale Cancer Center, New Haven, CT (STM and BC); and the Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (IVE and WG).
authors.forename: Brenda
authors.initials: B
authors.lastname: Cartmel
authors.affiliation: From the USDA/Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, ND (LJ, LDW, and MJP); the University of North Dakota, Grand Forks, ND (LKJ); the Yale School of Public Health and Yale Cancer Center, New Haven, CT (STM and BC); and the Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (IVE and WG).
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Picklo
authors.affiliation: From the USDA/Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, ND (LJ, LDW, and MJP); the University of North Dakota, Grand Forks, ND (LKJ); the Yale School of Public Health and Yale Cancer Center, New Haven, CT (STM and BC); and the Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (IVE and WG).
authors.forename: Igor V
authors.initials: IV
authors.lastname: Ermakov
authors.affiliation: From the USDA/Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, ND (LJ, LDW, and MJP); the University of North Dakota, Grand Forks, ND (LKJ); the Yale School of Public Health and Yale Cancer Center, New Haven, CT (STM and BC); and the Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (IVE and WG).
authors.forename: Werner
authors.initials: W
authors.lastname: Gellermann
authors.affiliation: From the USDA/Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, ND (LJ, LDW, and MJP); the University of North Dakota, Grand Forks, ND (LKJ); the Yale School of Public Health and Yale Cancer Center, New Haven, CT (STM and BC); and the Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (IVE and WG).
authors.forename: Leah D
authors.initials: LD
authors.lastname: Whigham
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood / Q000378:metabolism; D002338:Carotenoids / Q000008:administration & dosage / Q000097:blood / Q000172:deficiency / Q000378:metabolism*; D003430:Cross-Sectional Studies; D004032:Diet; D005260:Female; D005638:Fruit; D006801:Humans; D007700:Kinetics; D008297:Male; D009658:North Dakota; D009752:Nutritional Status; D010349:Patient Compliance; D010352:Patient Dropouts; D015203:Reproducibility of Results; D012867:Skin / Q000378:metabolism*; D013059:Spectrum Analysis, Raman; D014675:Vegetables
chemical_list: D015415:Biomarkers; D002338:Carotenoids