Pressure-Mediated Reflection Spectroscopy Criterion Validity as a Biomarker of Fruit and Vegetable Intake: A 2-Site Cross-Sectional Study of 4 Racial or Ethnic Groups

Stephanie B. Jilcott Pitts, Nancy E. Moran, Qiang Wu, Lisa Harnack, Neal E. Craft, Neil Hanchard, Ronny Bell, Stacey G Moe, Nevin Johnson, Justice Obasohan, Pamela L. Carr-Manthe, Melissa N. Laska

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


Background: Valid biomarkers of fruit and vegetable (FV) intake are needed for field-based nutrition research. Objectives: To examine criterion-related validity of pressure-mediated reflection spectroscopy as a proxy measure of FV intake, using plasma carotenoids and self-reported FV and carotenoid intake as primary and secondary criterion measures, respectively. Methods: Healthy adults 18-65 y of age, self-identifying as African American/black (n = 61), Asian (n = 53), white (n = 70), or Hispanic (n = 29), in North Carolina and Minnesota were recruited. Skin carotenoids were assessed via pressure-mediated reflection spectroscopy (Veggie Meter), skin melanin via spectrophotometer, and total plasma carotenoid concentration by HPLC-photodiode array detection. Self-reported carotenoid and FV intake was assessed using a semiquantitative FFQ. Relations between skin carotenoids, plasma carotenoids, FV, and carotenoid intake, with differences by race or ethnicity, age, sex, weight status, cholesterol, and melanin index, were examined by bivariate correlations and adjusted multivariate linear regressions. Results: The overall unadjusted correlation between skin and total plasma carotenoids was r = 0.71 and ranged from 0.64 (non-Hispanic black) to 0.80 (Hispanic). Correlations between skin carotenoids and self-reported FV intake ranged from 0.24 (non-Hispanic black) to 0.53 (non-Hispanic white), with an overall correlation of r = 0.35. In models adjusted for age, sex, racial or ethnic group, and BMI, skin carotenoids were associated with plasma carotenoids (R2 = 0.55), FV (R2 = 0.17), and carotenoid intake (R2 = 0.20). For both plasma carotenoid and FV measures, associations with skin carotenoids did not vary by race, but these relations did differ by skin melanin - those with lower melanin had a lower correlation between skin and plasma carotenoids. Conclusions: Reflection spectroscopy-assessed skin carotenoids may be a reasonable alternative to measurement of plasma carotenoids, a biomarker used to approximate FV intake.

Original languageEnglish (US)
Pages (from-to)107-116
Number of pages10
JournalJournal of Nutrition
Issue number1
StatePublished - Jan 1 2022

Bibliographical note

Funding Information:
This research was supported by the National Heart, Lung, and Blood Institute (NHLBI; grant R01HL142544) and by USDA Agricultural Research Service (CRIS 3092-51000-059-NEW2S; NEM). NIH grant UL1TR000114 from the National Center for Advancing Translational Sciences supported data management. The contents of this work are solely the responsibility of the authors and do not necessarily represent the official views of the USDA or NIH NHLBI.

Publisher Copyright:
© 2021 The Author(s).


  • biomarker
  • fruit and vegetable intake
  • melanin
  • noninvasive
  • nutrition assessment
  • skin carotenoids
  • skin tone

PubMed: MeSH publication types

  • Journal Article
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.


Dive into the research topics of 'Pressure-Mediated Reflection Spectroscopy Criterion Validity as a Biomarker of Fruit and Vegetable Intake: A 2-Site Cross-Sectional Study of 4 Racial or Ethnic Groups'. Together they form a unique fingerprint.

Cite this