Acide glycolique : avantages pour les soins de la peau, effets secondaires, etc.

Qu'est-ce que l'acide glycolique ?

If you’re looking to upgrade from a skincare amateur to a skincare pro, glycolic acid should be on your need-to-know list.

Glycolic acid is an alpha hydroxy acid (AHA), a natural acid derived from plants - in this case, sugar cane. It's made up of tiny molecules that can easily penetrate your skin barrier, helping to make it a particularly effective anti-ageing ingredient that promotes good skin health.

Avantages : que fait l'acide glycolique ?

So why exactly is glycolic acid good for your skin?

Dr Susan Mayou, consultant dermatologist at the Cadogan Clinic explains that glycolic acid works by dissolving the intercellular glue which holds your skin cells together.

"This results in the exfoliation of those cells - helping to remove dead skin and clear pores," she says.

Unlike mechanical exfoliants, such as face scrubs, glycolic acid is a gentler way to exfoliate your skin. This chemical exfoliant doesn’t require harsh scrubbing and instead removes skin cells while retaining moisture.

Mayou adds: "This helps brighten the skin's appearance, as light reflects better off a smooth skin surface, giving a more youthful and more radiant appearance."

Glycolic acid can benefit everyone's skin but people with the following skin issues may find it particularly helpful.

Comment utiliser l'acide glycolique dans votre routine de soins de la peau ?

These far-reaching skincare benefits may have you ready to dive head-first into a tub of glycolic acid. However, it's important to get your skin used to the product. Mayou advises first-timers to start with a gentle cleanser that contains a glycolic acid concentration of no more than 2% if you wish to use it every day.

Les produits à base d'acide glycolique se présentent sous plusieurs formes

Quelle est la fréquence d'utilisation de l'acide glycolique ?

Low to medium concentrations
Mayou cautions: "If using glycolic acid products containing 1-2% concentration, your skin should be able to tolerate this ingredient daily. However, it's important to build up gradually to avoid intolerance and sensitivity."

Les débutants peuvent commencer par appliquer de l'acide glycolique trois fois par semaine pendant une ou deux semaines. Si votre peau n'est pas irritée, vous pouvez passer à quatre fois par semaine pendant la même période. Continuez à augmenter progressivement la fréquence jusqu'à ce que l'acide glycolique fasse partie de votre routine quotidienne de soins de la peau.

Medium to high concentrations
Mayou says: "Products containing 10% and more should only be used once or twice a week as they are harsher and may cause a reaction. Remember, the higher the concentration the greater the peeling action."

If you have a generous skincare budget, professional glycolic acid peels contain the highest concentration and are a good option if you're looking to treat a specific skin issue. However, this means they carry a greater chance of irritation. You should aim to leave at least two weeks in between peels.

Vous pouvez également acheter des peelings à l'acide glycolique à domicile. Ils sont généralement plus abordables et contiennent des concentrations plus faibles. Lisez toujours l'étiquette et ne dépassez pas la fréquence d'utilisation recommandée.

Effets secondaires et risques

Irritation

Alors pourquoi faut-il faire attention à la quantité d'acide glycolique utilisée ? En bref, l'utilisation d'une trop grande quantité d'acide glycolique peut perturber votre peau. Pour certains types de peau, même de petites quantités peuvent entraîner des effets secondaires.

Si vous remarquez l'un de ces symptômes, arrêtez d'utiliser votre produit. Si vous souhaitez réessayer, laissez à votre peau le temps de se rétablir complètement, puis choisissez une concentration plus faible et limitez la fréquence d'application.

Dommages causés par le soleil

While glycolic acid offers great anti-ageing benefits, it can leave you more vulnerable to harmful UV rays. One study found that glycolic acid led to DNA damage, sunburn, and erythema - a skin rash caused by inflamed blood vessels - in participants, whereas, another exfoliating and anti-inflammatory skin treatment did not.

When glycolic acid removes the top layer of dead skin cells, it exposes the cells underneath, leaving them more sensitive to sun damage. Therefore, Mayou advises wearing a sunscreen with sun protection factor (SPF) 50+ every day before going outside. You will need to do this for as long as you use glycolic acid and for one week afterwards.

Peut-on utiliser l'acide glycolique pendant la grossesse ?

Glycolic acid is safe to use in pregnancy and breastfeeding. However, Mayou advises you use a low concentration and remember to apply SPF.

Pour en savoir plus

1. Campos, Pitassi, Gonçalves, Sant'Annhttps://pubmed.ncbi.nlm.nih.gov/33617668/am, and Correia "Clinical evaluation of the efficacy of a facial serum containing dioic acid, glycolic acid, salicylic acid, LHA, citric acid, and HEPES in treating post-inflammatory hyperchromia and controlling oily skin in patients with acne vulgaris".

2. Kornhauser, Wei, Yamaguchi, Coelho, Kaidbey, Barton, Takahashi, Beer, Miller et Hearing "The effects of topically applied glycolic acid and salicylic acid on ultraviolet radiation-induced erythema, DNA damage and sunburn cell formation in human skin" (Les effets de l'acide glycolique et de l'acide salicylique appliqués localement sur l'érythème induit par le rayonnement ultraviolet, les dommages à l'ADN et la formation de cellules de coup de soleil dans la peau humaine).