Examining Validity and Sensitivity of Pressure-Mediated Reflection Spectroscopy

Examining Validity and Sensitivity of Pressure-Mediated Reflection Spectroscopy as a Measure of Fruit and Vegetable Consumption in a Diverse Community

The central goal of this proposal is to examine validity and sensitivity of RS-assessed skin carotenoid status as a marker of F&V intake in a racially and ethnically diverse sample of individuals. First, investigators will examine the association (RS Device Validity) between RS-assessed skin carotenoids and the primary outcomes of objectively-measured plasma carotenoids and self-reported F&V consumption across four diverse groups: African-American/Black, Asian, White, and Hispanic/Latino (n=213). Then the investigators will conduct a randomized controlled trial to define the relative skin carotenoid responses (RS Device Sensitivity) across racial-ethnic groups, in comparison with plasma carotenoid responses. The investigators will conduct a 6-week randomized controlled trial of a carotenoid-containing juice intervention [placebo control, low and high dose juice (N=156). Finally, the genetic basis for racial/ethnic group differences in skin carotenoid responses to diet will be investigated through hypothesis-driven genomic analysis of participants from Aims 1 and 2.

Study Overview

• Status: Completed
• Conditions: Dietary Habits; Diet, Healthy
• Intervention / Treatment: Dietary supplement: High carotenoid juice; Dietary supplement: Placebo control - Apple juice

Detailed Description

A diet rich in fruits and vegetables (F&Vs) is associated with lower risk of nutrition-related chronic diseases and all-cause mortality. Despite these benefits, the US population under-consumes F&Vs, with particularly low intake in disadvantaged populations. Low F&V intake results in higher rates of nutrition-related chronic disease among disadvantaged populations when compared with more advantaged populations. Detecting and addressing inadequate F&V intake in these populations is needed to reduce such disparities. Yet, there is still no commonly used predictive, objective measure of F&V intake for surveillance or determination of policy or intervention effectiveness. The current objective, "gold standard" marker of F&V intake is blood carotenoid concentration-an expensive, time-intensive, and invasive measurement. Traditional methods of self-reported dietary assessment are imprecise and have diminished utility in rural and disadvantaged populations due to low literacy, numeracy, and internet connectivity. In the past decade, skin carotenoid status assessed by non-invasive resonance Raman spectroscopy (RRS) has emerged as a promising biomarker of F&V intake. Reflection spectroscopy (RS) is an improvement over RRS, offering stronger signals, faster data acquisition, and greater portability in a commercially available device (Veggie Meter, Longevity Link Corporation). However, a hurdle impedes use of RS in scientific studies: to date, nearly all of the non-invasive skin carotenoid validation has been conducted in non-Hispanic whites, primarily by RRS. Therefore, it is critical to evaluate RS in racially and ethnically diverse populations. The central goal of this proposal is to examine validity and sensitivity of RS-assessed skin carotenoid status as a marker of F&V intake in a racially and ethnically diverse sample of individuals. First, the investigators will examine the association (RS Device Validity) between RS-assessed skin carotenoids and the primary outcomes of objectively-measured plasma carotenoids and self-reported F&V consumption across four diverse groups: African-American/Black, Asian, White, and Hispanic/Latino (target n = 320 but due to Covid-19, N=213). Then the investigators will conduct a randomized controlled trial to define the relative skin carotenoid responses (RS Device Sensitivity) across racial-ethnic groups, in comparison with plasma carotenoid responses. The investigators will conduct an 6-week randomized controlled trial of a carotenoid-containing juice intervention [placebo control, low and high dose juice across 4 genetically-stratified racial-ethnic groups (goal n = 156). Finally, the genetic basis for racial/ethnic group differences in skin carotenoid responses to diet will be investigated through hypothesis-driven genomic analysis of participants from Aims 1 and 2. The results of this study will prepare RS for mass deployment in population surveillance studies and community-based intervention trials, ultimately leading to more accurate determination of the most effective strategies to reduce health disparities related to low F&V intake in the United States and beyond.

• Study Type: Interventional
• Enrollment (Actual): 162
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Minnesota
    • Minneapolis, Minnesota, United States, 55454
      • University of Minnesota
  • North Carolina
    • Greenville, North Carolina, United States, 27834
      • East Carolina University
  • Texas
    • Houston, Texas, United States, 77030
      • Baylor College of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Self-identified as one of the racial/ethnic groups of focus
• Read/speak English
• Between 18 and 65 years of age
• BMI 18.5-34.9 kg/m2
• Non-pregnant
• Non-lactating
• Healthy (no chronic disease)
• Not taking lipid-altering medication (medicines that lower cholesterol or triglycerides)
• Weight stable (have not gained or lost more than 15 pounds in the last 3 months).

Exclusion Criteria:

• Not of one of the four racial/ethnic groups of focus
• Not able to read/speak English
• Under 18 years of age or over 65 years of age, do not
• BMI less than 18.5 or more than 34.9 kg/m2
• Pregnant (or have been pregnant in the last 6 weeks)
• Lactating
• High blood sugar ( ≥126 mg/dl)
• Chronic disease such as cardiovascular disease, diabetes, chronic kidney disease, diabetes cancer other than non-melanoma skin cancer (within the last 5 years), or other weight-related chronic diseases.
• Taking medication that lowers cholesterol or triglycerides Diagnosed with/ treated for Crohn's disease.
• Not weight stable (gained or lost more than 15 pounds in the last three months)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low dose; 1 x 6 ounces of carotenoid-containing juice (6 mg carotenoids/6 oz)	Dietary supplement: High carotenoid juice; Juice with high carotenoids
Experimental: High dose; 2 x 6 ounces of carotenoid-containing juice (12 mg carotenoids/12 oz)	Dietary supplement: High carotenoid juice; Juice with high carotenoids
Placebo Comparator: Placebo; 12 ounces of apple juice (negligible carotenoids 0.06 mg/12 oz)	Dietary supplement: Placebo control - Apple juice; Juice with negligible carotenoids

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
3-week Change in Skin Carotenoid Status	Skin carotenoid level is a number from 0 to 800 that approximates carotenoids in the skin. The Veggie Meter device uses pressure mediated reflection spectroscopy to assess skin carotenoid level in the fingertip. Skin carotenoid levels are positively correlated with fruit and vegetable intake. A higher score generally indicates more fruit and vegetable intake, which is thought to be a better outcome. The primary outcome was change in skin carotenoid levels calculated by the skin carotenoid value at 3 weeks minus the value at baseline.	Change in skin carotenoid status from baseline to 3 weeks
6-week Change in Skin Carotenoid Status	Skin carotenoid level is a number from 0 to 800 that approximates carotenoids in the skin. The Veggie Meter device uses pressure mediated reflection spectroscopy to assess skin carotenoid level in the fingertip. Skin carotenoid levels are positively correlated with fruit and vegetable intake. A higher score generally indicates more fruit and vegetable intake, which is thought to be a better outcome. The primary outcome was change in skin carotenoid levels calculated by the value at 6 weeks minus the value at baseline.	Change in skin carotenoid status from baseline to 6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma carotenoid status	Assessed using high performance liquid chromatography	Change in plasma carotenoids from baseline to 3 weeks
Plasma carotenoid status	Assessed using high performance liquid chromatography	Change in plasma carotenoids from baseline to 6 weeks

Collaborators and Investigators

• Sponsor: East Carolina University
• Collaborators: Baylor College of Medicine; University of Minnesota
• Investigators: Principal Investigator: Stephanie B Jilcott Pitts, PhD, East Carolina University

Study record dates

Study Major Dates

• Study Start (Actual): June 28, 2021
• Primary Completion (Actual): April 14, 2022
• Study Completion (Actual): April 14, 2022

Study Registration Dates

• First Submitted: August 9, 2019
• First Submitted That Met QC Criteria: August 12, 2019
• First Posted (Actual): August 14, 2019

Study Record Updates

• Last Update Posted (Actual): June 15, 2023
• Last Update Submitted That Met QC Criteria: May 22, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Immune System Diseases; Hypersensitivity; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Protective Agents; Antioxidants; Carotenoids
• Other Study ID Numbers: 1R01HL142544-01A1 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified data will be shared with other researchers.
• IPD Sharing Time Frame: Data will be available to share with other investigators 12 months after study completion.
• IPD Sharing Access Criteria: Researchers must submit a plan for analysis, obtain Institutional Review Board approval and be approved by study investigators before data are released.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No