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

N/ACompletedNCT03202043

USDA Grand Forks Human Nutrition Research Center80 enrolled

Overview

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

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

Allocation

RANDOMIZED

Purpose

OTHER

Masking

NONE

Enrollment

Conditions

Overweight

Interventions

High dose vegetable juiceOTHER

High dose (13 fl oz) vegetable juice

Medium dose vegetable juiceOTHER

Medium dose (10 fl oz) vegetable juice

Low dose vegetable juiceOTHER

Low dose (5.5 fl oz) vegetable juice

Eligibility

Sex: ALLMin age: 18 YearsMax age: 65 YearsHealthy volunteers:

Medical Language ↔ Plain English

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

Locations (1)

USDA Grand Forks Human Nutrition Research Center

Grand Forks, North Dakota, United States

Outcomes

Primary Outcomes

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.

Time frame: 0, 4, 8 weeks

Secondary Outcomes

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.

Time frame: 0,4,8 weeks

Data from ClinicalTrials.gov

This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.