The Effect of Green Tea and Vitamin C on Skin Health

Not Applicable

Completed

• Conditions: Skin Cancer

• Registration Number: NCT01032031
• Lead Sponsor: University of Manchester

Brief Summary

There is little information on the effect of oral bioactive compounds on human skin clinically despite evidence of a beneficial effect from laboratory studies. The aim of this study is to examine the effect of oral bioactive compounds (green tea and vitamin C) on the health of human skin by measuring markers of skin health directly and skin nutrient uptake.

Detailed Description

There is little information on the effect of oral catechin, a nutritionally relevant bioactive compound, on skin health in humans in vivo despite considerable evidence for protective effects in experimental studies. Vitamin C is essential for skin health and stabilises catechins in the gut lumen. Ultraviolet radiation (UVR) in sunlight is a key environmental stressor impacting on skin health. Effects include acute inflammation and longer term photodamage.

OBJECTIVE: To examine the protective effect of catechin and vitamin C on UVR-induced inflammation.

STUDY DESIGN

(1) A double-blind randomised controlled nutritional study in 50 healthy volunteers. Volunteers will receive 3 months dietary supplement with high dose bioactive (n=25),or placebo (n=25).

The aim is to quantify the influence of catechin/vitamin C on:

1. UVR-induced inflammation

2. Leukocyte infiltration

3. Inflammatory mediators

4. Markers of photoageing

5. DNA damage

6. Bioavailability will also be assessed

(2) Bioavailability of catechin and vitamin C in skin and blood. Volunteers will receive active dietary supplement. Blood and urine samples will be taken over a period of 6 hours to determine blood bioavailability. Skin biopsies will also be taken to assess skin bioavailability. Volunteers will then receive 3 months of active dietary supplement followed by repeated sampling.

Study Timeline

• Study Start: 2009-03
• Study First Submitted: 2009-12-14
• Study First Submitted QC: 2009-12-14
• Study First Posted: 2009-12-15
• Primary Completion: 2012-08
• Study Completion: 2012-08
• Status Verified: 2016-03
• Last Update Submitted: 2016-03-07
• Last Update Posted: 2016-03-08

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 95

Inclusion Criteria

• Healthy adults
• Sun-reactive skin type I / II

Exclusion Criteria

• History of skin cancer
• History of a photosensitivity disorder
• History of a generalised skin disorder
• Sunbathing (including sunbeds) in the past 3 months
• Pregnancy
• Taking photoactive medicine
• Drink tea > 2 cups/day
• Taking nutritional supplements

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Change in the minimum erythemal dose (MED) of ultraviolet radiation.	3 months	The UV minimum erythemal dose (MED) will be determined for each study volunteer before and after nutritional supplementation to examine if the intervention can increase the MED and therefore protect against UV-induced erythema.

Secondary Outcome Measures

Name	Time	Method
Intergroup comparison of inflammatory mediators (cytokines/chemokines) in skin biopsy sections and blister fluid.	3 months
Intergroup comparison of histological biomarkers (leucocytes, markers of photoageing, DNA damage) in skin biopsy sections.	3 months
Nutrient (polyphenol) bioavailability in samples of skin, blood and urine.	3 months	Bioavailability will be assessed in volunteers participating in both the first (RCT) and second (non-randomised bioavailability) parts of the study.

Trial Locations

Locations (1)

Salford Royal NHS Foundation Trust; 🇬🇧 Manchester, United Kingdom