The Juice Study: Sensitivity of Skin Carotenoid Status to Detect Change in Intake

Sensitivity of Skin Carotenoid Status to Detect Changes in Intake of Varying Levels of Vegetables

This study is designed to see if drinking a tomato-based vegetable juice will increase skin carotenoids.

Study Overview

• Status: Completed
• Conditions: Overweight
• Intervention / Treatment: Other: High dose vegetable juice; Other: Medium dose vegetable juice; Other: Low dose vegetable juice; Other: Control bottled water

Detailed Description

The US Dietary Guidelines for Americans recommends that individuals consume approximately 2-4 c of vegetables each day to reduce risk of chronic disease, but current methods for assessing intake are either inaccurate (self-report) or invasive (blood carotenoid levels). Recent research indicates that skin carotenoid status may be a useful biomarker of vegetable intake, but the sensitivity to dose in unknown. In this study, we propose to test the dose-response of skin carotenoids to consumption of 3 different levels of vegetable juice (with a control group receiving water). We will test skin carotenoids in two ways: using resonance Raman spectroscopy (RRS), which we have previously validated, and with a new technique, pressure mediated reflection spectroscopy (RS; the "Veggie Meter"). We will compare the two techniques during an 8-week provided tomato-based juice intervention. Skin carotenoid readings will be compared to blood carotenoid concentrations and single nucleotide polymorphisms (SNPs) of genes related to the uptake, transport, and metabolism of carotenoids will be examined in blood and saliva.

• Study Type: Interventional
• Enrollment (Actual): 80
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • North Dakota
    • Grand Forks, North Dakota, United States, 58203
      • USDA Grand Forks Human Nutrition Research Center

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• BMI 18.5-29.9 kg/m2

Exclusion Criteria:

• weigh less than 110 lbs
• currently dieting to lose weight
• allergic to tomatoes or vegetables
• pregnant, lactating, or planning to become pregnant
• currently use tobacco products or vape
• eat more that 2 cups of vegetables per day
• have high blood sugar (≥200 mg/dL)
• have high blood pressure (≥140/90 mm Hg)
• have a medical condition such as diabetes or high blood pressure
• taking medication that lowers cholesterol or triglycerides

Study Plan

How is the study designed?

Design Details

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

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: High dose vegetable juice; Subject will consume high dose vegetable juice daily for 8 weeks.	Other: High dose vegetable juice; High dose (13 fl oz) vegetable juice
Experimental: Medium dose vegetable juice; Subject will consume medium dose vegetable juice daily for 8 weeks.	Other: Medium dose vegetable juice; Medium dose (10 fl oz) vegetable juice
Experimental: Low dose vegetable juice; Subject will consume low dose vegetable juice daily for 8 weeks.	Other: Low dose vegetable juice; Low dose (5.5 fl oz) vegetable juice
Other: Control bottled water; Subject will consume control bottled water daily for 8 weeks.	Other: Control bottled water; Control (12 fl oz) bottled water

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in skin carotenoid concentration as measured by pressure-mediated reflection spectroscopy (RS)	Pressure-mediated reflection spectroscopy (RS) is used to measure tissue carotenoids. RS intensity can be used as a measure for total carotenoid content in the measured tissue volume.	0, 4, 8 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Usual intake of carotenoid-rich foods and beverages	A 44-item food frequency questionnaire of the top carotenoid-rich foods and beverages will be developed to measure carotenoid intake from a person's usual diet.	0,4,8 weeks

Collaborators and Investigators

• Sponsor: USDA Grand Forks Human Nutrition Research Center

Publications and helpful links

Helpful Links

• Grand Forks Human Nutrition Research Center Current Nutrition Studies

Study record dates

Study Major Dates

• Study Start (Actual): April 6, 2018
• Primary Completion (Actual): May 21, 2019
• Study Completion (Actual): May 21, 2019

Study Registration Dates

• First Submitted: June 26, 2017
• First Submitted That Met QC Criteria: June 26, 2017
• First Posted (Actual): June 28, 2017

Study Record Updates

• Last Update Posted (Actual): May 16, 2022
• Last Update Submitted That Met QC Criteria: May 9, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Body Weight; Overweight
• Other Study ID Numbers: GFHNRC150

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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