Adding Polyphenol-rich Pulses to Daily Diet Improves Skin Health by Reshaping the Skin Microbiome

To Determine Whether Adding Polyphenol-rich Pulses to Daily Diet Improves Skin Health by Reshaping the Skin Microbiome and Lipids, and Reducing Oxidative Stress and Inflammation in Women

Skin health is influenced by the microbiome, lipids, oxidative stress, inflammation, and UV exposure. A 12-week trial with 48 women aged 45-65 will test if polyphenol-rich pulses improve skin health by affecting these factors. Using a white rice control diet, the study will measure skin parameters and analyze correlations with changes in lipids and microbiome, potentially proving the benefits of pulses.

Study Overview

• Status: Recruiting
• Conditions: Healthy
• Intervention / Treatment: Other: Pulse Diet; Other: Control Rice Diet

Detailed Description

Human skin is the largest organ in the body. The slow deterioration of skin appearance and its barrier function are the most prominent signs of human ageing. Cutaneous factors (microbiome and lipids) have immediate and direct impacts on skin health and functions. Intrinsic factors (oxidative stress and inflammation) and extrinsic ones (mostly UV irritation due to sun exposure) affect the skin chronically. Our preliminary research showed that six weeks of cranberry juice intake improved part of women's skin health parameters and decreased oxidative stress. Its activities on the skin correlated with changes in skin microbiome and epidermal lipids. Pulses, especially lentils and beans, are rich sources of polyphenols and fibers. However, there is no clinical evidence on whether adding a serving of cooked mixed pulses with high polyphenol content (lentils, red kidney bean, black beans, and pinto beans) to the diet affects skin health and the underlying causes of skin aging. Women make over 90% of the decisions on food purchases for their families. Skin health is a major concern for women because skin aging becomes visibly noticeable after age 30. The investigators hypothesize that polyphenol-rich pulses improve skin health by reshaping the cutaneous microbiome and lipids and suppressing inflammation and oxidative stress. This hypothesis will be tested in a 12-week clinical trial in 50 women aged 45-65 using a randomized controlled parallel design. The control diet will be formulated using white rice to match the calories and macronutrients of mixed pulses.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Liwei Gu, PhD; Phone Number: (352)2943730; Email: lgu@ufl.edu
• Study Contact Backup: Name: Ahmad Moussa, MS; Phone Number: (352) 392-0584; Email: moussaahmad@ufl.edu

Study Locations

• United States
  • Florida
    • Gainesville, Florida, United States, 32608
      • Recruiting
      • Food Science and Human Nutrition
      • Contact: Liwei Gu, phd; Phone Number: 352-294-3730; Email: lgu@ufl.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• BMI (18.5-29.9)
• Body weight ≥110 pounds
• Fitzpatrick skin type 1,2 and 3.

Exclusion Criteria:

• pregnancy
• breast-feeding
• impaired fasting glucose
• frequent alcohol use
• history of skin cancer
• sunbathing and the use of tanning bed, intake of vitamin/mineral supplements
• habitual high intake of fruits (≥ 2 cups daily)
• intake of medication that might influence the outcome of the study

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

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Pulse Diet; Participants will consume cooked pulses on an alternating basis over the 10-week intervention period. The pulses consist of 455 grams of the tri-bean blend (kidney, pinto, black bean), equivalent to 350 calories, and 225 grams of black lentils (400 calories).	Other: Pulse Diet; Participants will consume cooked pulses on an alternating basis over the 10-week intervention period. The pulses consist of 455 grams of the tri-bean blend (kidney, pinto, black bean), equivalent to 350 calories, and 225 grams of black lentils (400 calories).
Active Comparator: Control Rice Diet; Participants will consume cooked white rice (375 calories) over 10 weeks	Other: Control Rice Diet; Participants will consume cooked white rice (375 calories) over 10 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Skin sensitivity after UV radiation	Irradiation will be applied to dorsal skin (back, scapular region not typically exposed to the sun) with 2 times of minimal erythema dose using an FDA approved UVB phototherapy light and a UV light meter. At baseline and after 70 days, skin color will be measured before and 24 hours after irradiation. Skin color will be evaluated by a colorimeter. The a*-value (red/green-axis) is a measure of reddening (erythema).	84 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
skin transepidermal water loss	Skin transepidermal water loss will be measured using a Tewameter to evaluate the water barrier function of the skin. The Tewameter measures the density gradient of the water evaporation from the skin (g/h/m^2).	84 days
skin erythema and melanin index	Skin erythema and melanin index ((Arbitrary Mexameter Units on a scale of 0-999) will be assessed with Mexameter. These two components are mainly responsible for the color of the skin. They are measured by reflectance.	84 days
inflammation biomarkers	Plasma concentration levels (pg/mL) of IL-6 proteins will be analyzed as inflammation biomarkers using ELISA kits.; Plasma concentration levels (mg/mL) of C-reactive proteins will be analyzed as inflammation biomarkers using ELISA kits.	84 days
oxidative stress biomarkers	Concentration of Malondialdehyde (nmol/mL) in plasma will be determined as a marker of lipid peroxidation using a photometric method.	84 days
skin microbiome	For skin swabbing, a 3x3-cm square on a forearm will be swabbed with a cotton swab soaked in 0.9% sodium chloride with 0.1% Tween-20 in a Z-stroke manner	84 days
skin hydration	Skin hydration (Arbitrary Units (AU) on a scale of 0-120) will be measured using a Skin Corneometer.	84 days
skin pH	Skin pH will be measured using a Skin-pH-Meter.	84 days

Collaborators and Investigators

• Sponsor: University of Florida

Study record dates

Study Major Dates

• Study Start (Estimated): April 24, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: July 26, 2024
• First Submitted That Met QC Criteria: August 2, 2024
• First Posted (Actual): August 5, 2024

Study Record Updates

• Last Update Posted (Actual): May 6, 2026
• Last Update Submitted That Met QC Criteria: April 29, 2026
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: Women; Pulse; Skin health
• Other Study ID Numbers: IRB202401105

Drug and device information, study documents

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