The double-blind, placebo controlled study, published in the European Journal of Dermatology , recruited 49 healthy subjects (10 fair-skinned, 19 phenotype III, 20 phenotype IV) and induced UV skin burn on the inner-forearms before supplementation with GliSODin or a placebo, and then one a week for four weeks with continued daily supplementation.
The researchers, from Cutanees Engineering and Research Laboratory, the Federal Research Institute at the University of Franche-Comte, and Bioexigence, all of Besancon, France, report that GliSODin supplementation resulted in a 7.6 per cent increase in the minimum exposure to UV rays necessary to produce skin burn.
"This study confirms the efficacy of GliSODin in the prevention of the consequences of oxidative stress resulting from exposure to the sun.
This efficacy is of particular interest for phototypes II (fair-skinned) that represent a major part of the consultations in dermatology," wrote the researchers.
SOD has a different mode of action to vitamins.
Dubbed 'the enzyme of life' when first discovered in 1968, it is the first antioxidant mobilised by the cell for defence.
It is thought to be more powerful than antioxidant vitamins as it activates the body's production of its own antioxidants, including catalase and glutathione peroxidase.
GliSODin, the combination of SOD extracted from cantaloupe melon and wheat gliadin, is patented and trademarked by Paris-based Isocell.
In North America PL Thomas distributes the ingredient.
The new study, using chromatography to measure skin colour and videocapillaroscopy to assess inflammation, found that people with fair skin (phototypes II) endured a longer light exposure to create the skin burn after supplementation (7.6 per cent), as compared to those taking a placebo.
People with darker skins - phototype III and IV - had less benefits with a 0.7 per cent and no change, respectively.
Skin redness induced by the skin burn disappeared more quickly in the GliSODin group - 8.4 per cent quicker than placebo for the phototype II - and the regeneration of capillaries in the skin, a measure of recovery and reduction in inflammation, was 33 per cent higher in the GliSODin group compared to placebo for the same phototype.
"This study clearly shows the potential for GliSODin to help inhibit the oxidative stress caused by UV radiation, particularly for light-skinned and sun-sensitive individuals.
As a nutricosmetic, it is a 24/7 prophylaxis which can complement topicals, which may not be always applied before going out into the sun," said Paul Flowerman, president of PL Thomas.
"However, GliSODin is a complementary supplement to good sun-protective measures.
We do not suggest that this is a sun-screen, and strongly recommend topical lotions and protective clothing when exposed to the sun," he added.
In a previous open study conducted in France in 2004 on 150 patients supervised by 40 dermatologists, positive results on people with light sun allergies were reported for supplementation with the combined SOD-gliadin biopolymer.
Source: European Journal of Dermatology March-April 2007, Volume 17, Number 2, Pages 10-11 "Could a photobiological test be a suitable method to assess the anti-oxidant effect of a nutritional supplement (GliSODin)?"
Authors: S. Mac-Mary, J.M. Sainthillier, C. Courderot-Masuyer, P. Creidi, P. Humbert