Cosmetic bluff?
Arild Hoksnes
Photo: HEXA Kroppspleie og Slankesenter
Including vitamin E as an ingredient in cosmetic products probably has no effect on the skin. This is in stark contrast to the cosmetic industry's marketing of vitamin E's favourable impact against wrinkles, to name but one example.
The marketing campaigns for a countless number of cosmetic products, including the so-called anti-wrinkle creams and sun creams, claim that the inclusion of vitamin E can help the skin remain softer and younger looking. The most commonly used ingredient of this type is vitamin E acetate.
A research team from NTNU, led by chemists Vassilia Partali and Hans-Richard Sliwka, has tried to find chemical compositions that would be more active as antioxidants than either vitamin E or naturally occurring carotenoids alone. When they checked the scientific literature, the team found that a series of E esters would be more or less inactive without the activated decomposition that takes place in the intestine when we take in these compositions through food. The skin does not contain the necessary enzymes that can activate vitamin E esters. This means that vitamin E esters can not have the effects claimed in the marketing of these products.
A marketing gimmick?
The researchers raise the question: "When vitamin E esters are so inactive on the skin, why are they then included in cosmetic products at all unless this is just a marketing gimmick?"
Carotenoids are normally used as additions in fodder for salmon and poultry to create the desired colour in meat and eggs, while vitamin E is a useful food stabiliser (E307), but they are all found in cosmetics and sun creams.
"Antioxidants often have complimentary characteristics and mixtures of antioxidants often show greater activity than the sum of the individual substances," says Hans-Richard Sliwka.
"We are trying to combine natural antioxidants such as vitamin E, carotenoids and selenium, either directly or via natural carrier molecules. Some of our new substances resemble a highly unsaturated fat, which is presumably self-stabilising because of 'inbuilt' antioxidants. Fat is easily absorbed in the intestine and we hope in this way to increase the absorption or effect."
Contacts at NTNU: Hans-Richard Sliwka
Tel.: +47 73 59 56 00
E-mail: hrs@nvg.ntnu.no
Vassilia Partali
Tel.: +47 73 59 62 09
E-mail: vassilia.partali@chembio.ntnu.no