The Effect of Green Tea and Vitamin C on Skin Health
|Skin Cancer||Dietary Supplement: Green tea + vitamin C high dose Dietary Supplement: Placebo capsule|
|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|
- 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.
- 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.
|Study Start Date:||March 2009|
|Study Completion Date:||August 2012|
|Primary Completion Date:||August 2012 (Final data collection date for primary outcome measure)|
|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
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:
- UVR-induced inflammation
- Leukocyte infiltration
- Inflammatory mediators
- Markers of photoageing
- DNA damage
- 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.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01032031
|Salford Royal NHS Foundation Trust|
|Manchester, United Kingdom|
|Principal Investigator:||Lesley E Rhodes, MBBS, MD||University of Manchester|