The Effect of Green Tea and Vitamin C on Skin Health

Skin Cancer Clinical Trial

Official title:

The Effect of Dietary Bioactive Compounds on Skin Health in Humans in Vivo

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01032031
• Other study ID #: BB/G005575/1
• Secondary ID: UKCRN 6911
• Status: Completed
• Phase: N/A
• First received: December 14, 2009
• Last updated: March 7, 2016
• Start date: March 2009
• Est. completion date: August 2012

Study information

• Verified date: March 2016
• Source: University of Manchester
• Contact: n/a
• Is FDA regulated: No
• Health authority: United Kingdom: Research Ethics Committee
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 95
• Est. completion date: August 2012
• Est. primary completion date: August 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 65 Years

Eligibility

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

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Skin Cancer

Intervention

Dietary Supplement:
• Green tea + vitamin C high dose
One green tea capsule (1250mg catechin) and one vitamin C tablet (100mg) daily for 3 months
• Placebo capsule
One capsule daily for 3 months

Locations

Country	Name	City	State
United Kingdom	Salford Royal NHS Foundation Trust	Manchester

Sponsors (3)

Lead Sponsor	Collaborator
University of Manchester	University of Bradford, University of Leeds

Country where clinical trial is conducted

United Kingdom, 

References & Publications (4)

Clarke KA, Dew TP, Watson RE, Farrar MD, Bennett S, Nicolaou A, Rhodes LE, Williamson G. High performance liquid chromatography tandem mass spectrometry dual extraction method for identification of green tea catechin metabolites excreted in human urine. J — View Citation

Clarke KA, Dew TP, Watson RE, Farrar MD, Osman JE, Nicolaou A, Rhodes LE, Williamson G. Green tea catechins and their metabolites in human skin before and after exposure to ultraviolet radiation. J Nutr Biochem. 2016 Jan;27:203-10. doi: 10.1016/j.jnutbio. — View Citation

Farrar MD, Nicolaou A, Clarke KA, Mason S, Massey KA, Dew TP, Watson RE, Williamson G, Rhodes LE. A randomized controlled trial of green tea catechins in protection against ultraviolet radiation-induced cutaneous inflammation. Am J Clin Nutr. 2015 Sep;102 — View Citation

Rhodes LE, Darby G, Massey KA, Clarke KA, Dew TP, Farrar MD, Bennett S, Watson RE, Williamson G, Nicolaou A. Oral green tea catechin metabolites are incorporated into human skin and protect against UV radiation-induced cutaneous inflammation in associatio — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in the minimum erythemal dose (MED) of ultraviolet radiation.	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.	3 months	No
Secondary	Intergroup comparison of inflammatory mediators (cytokines/chemokines) in skin biopsy sections and blister fluid.		3 months	No
Secondary	Intergroup comparison of histological biomarkers (leucocytes, markers of photoageing, DNA damage) in skin biopsy sections.		3 months	No
Secondary	Nutrient (polyphenol) bioavailability in samples of skin, blood and urine.	Bioavailability will be assessed in volunteers participating in both the first (RCT) and second (non-randomised bioavailability) parts of the study.	3 months	No