The Effect of Green Tea and Vitamin C on Skin Health

This study has been completed.
Sponsor:
Collaborators:
University of Leeds
University of Bradford
Information provided by (Responsible Party):
Lesley Rhodes, University of Manchester
ClinicalTrials.gov Identifier:
NCT01032031
First received: December 14, 2009
Last updated: August 21, 2013
Last verified: August 2013

December 14, 2009
August 21, 2013
March 2009
August 2012   (final data collection date for primary outcome measure)
Change in the minimum erythemal dose (MED) of ultraviolet radiation. [ Time Frame: 3 months ] [ Designated as safety issue: No ]
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.
Degree of clinical protection against UVR-induced erythema [ Time Frame: 3 months ] [ Designated as safety issue: No ]
Complete list of historical versions of study NCT01032031 on ClinicalTrials.gov Archive Site
  • Intergroup comparison of inflammatory mediators (cytokines/chemokines) in skin biopsy sections and blister fluid. [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  • Intergroup comparison of histological biomarkers (leucocytes, markers of photoageing) in skin biopsy sections. [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  • Nutrient (polyphenol) bioavailability in samples of skin, blood and urine. [ Time Frame: 3 months ] [ Designated as safety issue: No ]
    Bioavailability will be assessed in volunteers participating in both the first (RCT) and second (non-randomised bioavailability) parts of the study.
  • Intergroup comparison of inflammatory mediators [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  • Intergroup comparison of histological biomarkers [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  • Nutrient bioavailability [ Time Frame: 3 months ] [ Designated as safety issue: No ]
Not Provided
Not Provided
 
The Effect of Green Tea and Vitamin C on Skin Health
The Effect of Dietary Bioactive Compounds on Skin Health in Humans in Vivo

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.

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. 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.

Interventional
Not Provided
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Skin Cancer
  • Dietary Supplement: Green tea + vitamin C high dose
    One green tea capsule (1250mg catechin) and one vitamin C tablet (100mg) daily for 3 months
  • Dietary Supplement: Placebo capsule
    One capsule daily for 3 months
  • Active Comparator: Green tea + vit C high dose
    Intervention: Dietary Supplement: Green tea + vitamin C high dose
  • Placebo Comparator: Placebo
    Intervention: Dietary Supplement: Placebo capsule
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 association with reduced production of pro-inflammatory eicosanoid 12-hydroxyeicosatetraenoic acid. Br J Nutr. 2013 Jan 28:1-10. [Epub ahead of print]

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
95
August 2012
August 2012   (final data collection date for primary outcome measure)

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
Both
18 Years to 65 Years
Yes
Contact information is only displayed when the study is recruiting subjects
United Kingdom
 
NCT01032031
BB/G005575/1, UKCRN 6911
No
Lesley Rhodes, University of Manchester
University of Manchester
  • University of Leeds
  • University of Bradford
Principal Investigator: Lesley E Rhodes, MBBS, MD University of Manchester
University of Manchester
August 2013

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP