title: Chocolate flavanols and skin photoprotection: a parallel, double-blind, randomized clinical trial.
abstract: BACKGROUND
  Solar ultraviolet (UV) radiation has deleterious effects on the skin, including sunburn, photoaging and cancer. Chocolate flavanols are naturally-occurring antioxidant and anti-inflammatory molecules that could play a role in preventing cutaneous UV damage. We investigated the influence of 12-week high-flavanol chocolate (HFC) consumption on skin sensitivity to UV radiation, measured by minimal erythema dose (MED). We also evaluated skin elasticity and hydration.
  
  
  METHODS
  In this 2-group, parallel, double-blind, randomized controlled trial, 74 women aged 20-65 years and Fitzpatrick skin phototypes I or II were recruited from the general community in Quebec City, for randomization to either HFC (n = 33) or low-flavanol chocolate (LFC) (n = 41). A blocked randomisation (4), considering date of entry, skin type and age as factors, generated a sequentially-numbered allocation list. Study participants and research assistants were blinded. Totally, 30 g of chocolate were consumed daily for 12 weeks, followed by a 3-week washout period. MED was assessed at baseline and at 6, 9, 12 and 15 weeks. Main outcome was changes in MED at week 12.
  
  
  RESULTS
  33 participants in the HFC group and 41 in the LFC group were analyzed with 15 weeks of follow-up. Both groups showed similarly-increased MED at 12 weeks (HFC: 0.0252 ± 0.1099 J/cm2 [mean ± standard deviation (SD)]; LFC: 0.0151 ± 0.1118; mean difference (MD): 0.0100 J/cm2; 95% confidence interval (CI): -0.0417 to 0.0618). However, after 3-week washout, the HFC group presented decreased MED (-0.0248 ± 0.1145) whereas no effect was seen in the LFC group (0.0168 ± 0.1698) (MD: -0.0417; 95% CI: -0.1106 to 0.0272). Net temple elasticity increased slightly but significantly by 0.09 ± 0.12 mm in the HFC group at 12 weeks compared to 0.02 ± 0.12 mm in the LFC group (MD: 0.06; 95% CI: 0.01 to 0.12 ). No significant adverse events were reported.
  
  
  CONCLUSIONS
  Our study failed to demonstrate a statistically-significant protective effect of HFC vs. LFC consumption on skin sensitivity to UV radiation as measured by MED.
  
  
  BACKGROUND
  ClinicalTrials.gov identifier: NCT01444625.
authors: Jaime Andres
authors: JA
authors: Mogollon
authors: Catherine
authors: C
authors: Boivin
authors: Simone
authors: S
authors: Lemieux
authors: Claudine
authors: C
authors: Blanchet
authors: Joël
authors: J
authors: Claveau
authors: St, François d'Assise Hospital, Centre hospitalier universitaire de Québec (CHUQ), Quebec, QC, Canada. sylvie.dodin@fmed.ulaval.ca.
authors: Sylvie
authors: S
authors: Dodin
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000494:pharmacology; D002099:Cacao; D004311:Double-Blind Method; D004548:Elasticity; D004890:Erythema / Q000517:prevention & control; D005260:Female; D006801:Humans; D008875:Middle Aged; D059808:Polyphenols / Q000097:blood / Q000627:therapeutic use*; D011792:Quebec; D011837:Radiation-Protective Agents / Q000627:therapeutic use*; D012867:Skin / Q000187:drug effects / Q000528:radiation effects*; D012879:Skin Physiological Phenomena; D013471:Sunburn / Q000517:prevention & control*; D014466:Ultraviolet Rays
chemical_list: D000975:Antioxidants; D059808:Polyphenols; D011837:Radiation-Protective Agents