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Cosmetic active ingredients and the sun: FRIENDS or ENEMIES?

What is the link between AHAs, like glycolic acid, bergamot essential oil, and Retinol? Photosensitization. With them on the skin, avoid the sun to prevent redness, burns, or hyperpigmented spots. You may wonder if this incompatibility has a real scientific basis? Well, you're right to ask this question because it's true, but there are exceptions. Novexpert's analysis activated!


With AHAs and Retinol on the skin, the sun is a No-Go

Glycolic acid (and Peels in general) as well as Retinol disassociate the cells from the first layers of the epidermis to stimulate their renewal. Result: a radiant complexion is yours. The downside: the skin's barrier function being temporarily altered, the skin is left"bare", at the mercy of UV rays which then penetrate deeper into the skin.

And that's not insignificant because sun exposure after peeling can result in redness or irritation, or even overstimulation of melanocytes (the melanin factories) responsible for hyperpigmented spots.

Concretely, Peels and Retinol are preferably done in spring (and autumn) and in any case only in the evening, with the application of sunscreen the next day if you expose yourself.


Essential but definitely not in the sun

For bergamot essential oil (as for several citrus essential oils obtained from the zest), reactions with the sun occur deep within the cells themselves.

It's the furocoumarins, and particularly bergapten in the case of bergamot, that make it photosensitizing. They combine with the DNA of keratinocytes (the cells of the epidermis) and absorb UV energy, thus causing irreversible damage to the skin (spots, premature wrinkles, skin allergies).

Fortunately, chemists have more than one trick up their sleeve and have managed to remove furocoumarins from essential oils that contain them, but it's not automatic.

So when you use essential oils, make sure they are free from photosensitizing molecules. And don't forget to seek advice from a healthcare professional (pharmacist, naturopath) because although essential oils are 100% natural, they are not suitable for everyone. Golden rules with essential oils:

Pregnant and breastfeeding women should avoid them.

For children, it's also a no unless there's an exception depending on the essential oil and the child's age.

Cheap essential oils, steer clear!

Orally, be extremely careful.

For topical application, never use them undiluted, always dilute them in a neutral vegetable oil or a cosmetic base, and inquire about the dosage.

And at Novexpert, is it still a no for essential oils?

Novexpert has chosen to exclude essential oils from its formulation charter.

Why? Because they are highly allergenic despite being natural compounds.

This allergenic potential comes from the fact that an essential oil can contain from 200 to 600 different molecules, with just one of them capable of causing an allergy (statistical law).

So you understand that essential oils do not allow us to be used by all skin types, especially sensitive skin, nor do they allow us to have hypoallergenic products.

Furthermore, at Novexpert, we want our products to be compatible with pregnant and breastfeeding women. However, the majority of essential oils are potentially neurotoxic and can harm the smooth progress of pregnancy. Indeed, they have the ability to penetrate the layers of the skin to the bloodstream... and thus to the unborn child.

Moreover, some essential oils have an effect on the hormonal system (known as hormone-like). They are thus considered Endocrine Disruptors and are therefore prohibited from our formulation charter, and that's non-negotiable.


The sun, the archenemy of Vitamin C? Are you sure?

It's a myth that's hard to debunk, but we're going to do it right away: a formula with vitamin C is not necessarily incompatible with the sun!

If a brand tells you not to expose yourself after using its vitamin C serum on the pretext that vitamin C is sensitive to the sun, it's false. It's the product itself that is incompatible with sun exposure. Why? Because standard vitamin C manages to penetrate the skin and thus be effective only at a very acidic pH, around 3, knowing that the pH of lemon juice is 2.5, it's so acidic that it's too acidic for the skin, which then finds itself "bare" as after the application of a Peel... do you remember what Peeling and sun exposure can result in?

Thanks to our stabilized vitamin C complex, it is protected from destruction, especially by light and heat.


And to completely reassure you:

  • the pH of the Booster being close to that of the skin, it is therefore compatible with all skin types, even sensitive skin.
  • the vitamin C booster is certified non-photoallergenic, non-phototoxic, and therefore non-photosensitive.

Our Vitamin C Booster Serum, a source of vitamin C for your skin, 365 days a year, whatever the weather, whatever your skin type!

In the morning, the Vitamin C Booster Serum alone or before your usual cream.

In the evening, after cleansing your skin, apply the Green Tea Polyphenol Booster Serum alone or before your usual cream.

Today we know it.

Beautiful skin is, above all,
healthy skin.

Creating another way of achieving beauty is a necessity. For 15 years, Novexpert has been committed to demanding cosmetics based on science and facts. They are researchers fascinated by science, passionate about skin and health.

And here is what we do.
Explain, transmit and learn: how the body works, how the skin works.
Formulate, without compromising: 100% healthy products, because they are 100% of natural origin, highly concentrated active ingredients.
Test, study, adjust, for treatments with clinically proven effectiveness.
Support, provide what is missing in a serum, a food supplement or a treatment: nutrition, sleep, daily advice and recommendations.
Create a new type of treatment to take care of your skin.

Novexpert, Knowledge engages us.

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