Résumé : |
In vitro studies have demonstrated the biological activity of avocado extract with high polyphenol content in a key area of eye care and these have been confirmed by two clinical studies.
Dark circles and bags under the eyes are a common and universal aesthetic concern, which affects both men and women, regardless of age and ethnic origin. Although they are not of concern in terms of their effects on health, these conditions can be embarrassing and affect quality of life. They influence the overall appearance of the face, making it look tired, sad and older. They are therefore of significant cosmetic concern, especially for women.
The aetiology of dark circles and bags under the eyes is complex and multi-factorial. It combines intrinsic factors, such as ethnic origin or heredity, and extrinsic or lifestyle-related factors such as fatigue, lack of sleep, stress, smoking, excess alcohol consumption, hormonal changes, diseases, infections, allergies, etc.
Physiologically-speaking, there are the two main causes behind the appearance of dark circles and bags under the eyes: microcirculation and hyperpigmentation.
Microcirculation, or superficial microvascularisation in the eye area, is conducive to blood stagnation (or congestion) and dilatation, and is responsible for oedema, which is characterised by the collection of fluid in the tissue. A recent study showed an increase in dilatation of the blood vessels and the number of capillaries by videocapillaroscopy in subjects with persistent under-eye dark circles.1 These disorders are believed to be exacerbated by inflammation of the eye area.
Other secondary causes have also been described. The thin, transparent skin in the eye area could contribute to the visual appearance of dark circles as dilatation of the blood and hyperpigmentation can be seen more easily. In effect, compared to the rest of the face, the eyelid dermis contains less collagen, elastin and glycosaminoglycans.
The anatomy of the eye area itself is a contributing factor, as the bone structure can create a shadow effect. An effect which may be further accentuated by age-related or chronic photodamage-related skin slackening.
Oxidative stress could also play a role aggravating the appearance of dark circles, as blood vessel dilatation can lead to the release of heme and other metabolites into the tissue. Under oxidative stress, this leads to cytotoxic and proinflammatory effects, which are likely to exacerbate vasodilatation and hyperpigmentation.
Finally, bags are characterised even more by fluid collection and protrusion of fatty tissue in particular, which may be made worse by weakening of the septum as we age.
This article presents the studies that demonstrated the biological activity of avocado extract with high polyphenol content. This active ingredient, produced from avocado cake by extraction, comes in liquid form.
The effect of avocado polyphenols has been demonstrated by various in vitro biological models on the causes behind the formation of dark circles and bags under the eyes. These results were confirmed by two clinical studies which showed an effect from this active ingredient which corrected the appearance of dark circles and bags under the eyes. |