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The Effect of Green Tea and Vitamin C on Skin Health

This study has been completed.
University of Leeds
University of Bradford
Information provided by (Responsible Party):
Lesley Rhodes, University of Manchester Identifier:
First received: December 14, 2009
Last updated: March 7, 2016
Last verified: March 2016
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.

Condition Intervention
Skin Cancer Dietary Supplement: Green tea + vitamin C high dose Dietary Supplement: Placebo capsule

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: The Effect of Dietary Bioactive Compounds on Skin Health in Humans in Vivo

Resource links provided by NLM:

Further study details as provided by Lesley Rhodes, University of Manchester:

Primary Outcome Measures:
  • Change in the minimum erythemal dose (MED) of ultraviolet radiation. [ Time Frame: 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:
  • Intergroup comparison of inflammatory mediators (cytokines/chemokines) in skin biopsy sections and blister fluid. [ Time Frame: 3 months ]
  • Intergroup comparison of histological biomarkers (leucocytes, markers of photoageing, DNA damage) in skin biopsy sections. [ Time Frame: 3 months ]
  • Nutrient (polyphenol) bioavailability in samples of skin, blood and urine. [ Time Frame: 3 months ]
    Bioavailability will be assessed in volunteers participating in both the first (RCT) and second (non-randomised bioavailability) parts of the study.

Enrollment: 95
Study Start Date: March 2009
Study Completion Date: August 2012
Primary Completion Date: August 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Green tea + vit C high dose 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 Comparator: Placebo Dietary Supplement: Placebo capsule
One capsule daily for 3 months

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.


(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.


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

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
  Contacts and Locations
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Please refer to this study by its identifier: NCT01032031

United Kingdom
Salford Royal NHS Foundation Trust
Manchester, United Kingdom
Sponsors and Collaborators
University of Manchester
University of Leeds
University of Bradford
Principal Investigator: Lesley E Rhodes, MBBS, MD University of Manchester
  More Information

Responsible Party: Lesley Rhodes, Professor of Experimental Dermatology, University of Manchester Identifier: NCT01032031     History of Changes
Other Study ID Numbers: BB/G005575/1
UKCRN 6911 ( Registry Identifier: UK Clinical Research Network )
Study First Received: December 14, 2009
Last Updated: March 7, 2016

Keywords provided by Lesley Rhodes, University of Manchester:
Green tea
Vitamin C
Ultraviolet radiation

Additional relevant MeSH terms:
Skin Neoplasms
Neoplasms by Site
Skin Diseases
Ascorbic Acid
Growth Substances
Physiological Effects of Drugs
Molecular Mechanisms of Pharmacological Action
Protective Agents processed this record on June 22, 2017