The Effect of Dietary Bioactive Compounds on Skin Health in Humans in Vivo
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
(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
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.
Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Basic Science
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.
Lesley E Rhodes, MBBS, MD
University of Manchester
United Kingdom: Research Ethics Committee