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La Rosée cosmétiques

Hydration is part of our DNA, because it's the secret of beautiful skin.

Do you want to understand why? You are in the right place!

We will explain to you how hydration works, why it is so important, and how to ensure your skin has optimal hydration.

How does hydratation work?

In the skin, there is water

The skin is a cutaneous barrier, that above all, protects the body. It contains about 67% water, with variations depending on age:

  • Around 74% for a newborn
  • Versus 62% for an elderly person

These differences largely explain the differences in skin appearance.

  • Part of this water is called "free", it is mobile and can evaporate.
  • Another part is "immobile" water, it can not evaporate because it is fixed to the structures of the dermis.

A balance between water intake and water loss is necessary to maintain the water content within the body.

Dans peau il y a eau : un équilibre entre les apports et les pertes en eau est nécessaire pour avoir une belle peau - La Rosée

It is all about the structure!

It is the structure of our skin that allows us to retain the water that our body needs and maintain a good level of hydration so that the skin remains supple, soft and toned.

Our skin is made up of three main overlapping layers: the epidermis, which contains the hydrolipidic film on the surface, the dermis and the hypodermis, which is even deeper.

Why hydrate your skin?

To compensate for permanent evaporation

The water stored in the dermis is transported to the epidermal cells via blood microcirculation and the proteins called aquaporins maintain the water balance between these layers.

This water, which is present in gaseous form, constantly evaporates through perspiration and transpiration (respiratory exchange that takes place through the skin). This phenomenon is called transepidermal water loss (TEWL) and represents about a half-liter per day!

This daily water loss must be compensated, in order to maintain the skin's general balance.

To prevent the alteration of the hydrolipidic film

Other factors can disrupt good skin hydration: aggressive cleansing, lifestyle, pollution, hard water, hot showers... The hydrolipidic film is often put to the test!

When this film is altered, the epidermis is no longer properly protected and water evaporates. The skin becomes dehydrated and more sensitive. It then needs to be rehydrated to repair it..

To maintain beautiful, healthy skin

Good hydration leaves the skin feeling good and protected.

In the long term, it also helps:

Slow down skin aging.

Over time, the structure of the dermis weakens and the skin thins. Skin tissue loses volume and elasticity: wrinkles gradually form.

Regular, suitable hydration helps fight external aggressions and makes skin more resistant to combating skin aging.

To ensure cell renewal.

Cell renewal is a natural process that the skin does about every 28 days. It is essential for healthy skin.

Our skin cells are continuously produced in the deepest layer of the epidermis. They then gradually migrate to the surface. Their journey ends in the outermost layer of the epidermis: the stratum corneum. At this point, our skin sheds its cells because they have died. This is known as desquamation. In this way, the skin renews itself and its appearance becomes brighter.

When the skin is properly hydrated, the dead cells in the stratum corneum can be removed more easily and the skin can regenerate better.

Hydrater sa peau est essentiel pour avoir une belle peau en bonne santé - La Rosée

How to hydrate your skin properly?

Achieve in-depth hydration through oral water intake

This provides deep hydration at the dermal level. You should therefore drink at least 1.5 liters of water throughout the day! This hydration compensates for the insensible water loss.

Hydrate the epidermis and stratum corneum with cosmetic care.

Hydrating care helps to strengthen the stratum corneum and rebalance the hydrolipidic film to prevent dehydration by providing lipids and/or water depending on the skin's needs.

Hydrating care works in two ways:

  • By limiting water loss from the epidermis, thanks to hydrophilic film formers: they deposit a small, moist insulating layer to keep water in the epidermis while allowing the skin to breathe. These are contained in vegetable glycerin and plant waxes, which are particularly interesting due to their hydrating effects.
  • By strengthening the skin's resistance to dehydration, thanks to emollients: these active ingredients fill the micro-cracks in the lipid cement through which water evaporates. Only natural emollients such as butter and vegetable oils are effective as they penetrate deep into the skin (shea butter, almond oil, coconut oil, jojoba oil, sunflower oil for example).

As you can see, choosing the right skincare products is crucial!

Bien hydrater sa peau passe par l'hydratation de l'épiderme et de la couche cornée grâce aux soins cosmétiques - La Rosée

How to choose the right skincare products?

All skin types, even the oiliest, need hydration care because they are all exposed to water loss that must be compensated.

The drier the skin, the more it will need fatty emollient agents. No matter how nourishing the products are, if the skin is hydrated with poorly chosen care products, it will remain dull.

To get maximum effectiveness, you need to use the right products suited to your skin type and condition.

Know your skin type and condition to provide an adapted response

  • Skin type is genetic. It corresponds to the physiological nature of the skin. It can evolve over time.
  • Skin condition is a transient and punctual state of the skin. It appears due to external factors like temperature changes, lifestyle, an overly harsh beauty routine, or internal factors like hormones, emotions and skin aging.

Rely on cosmetic tests

Clinical tests

In order to claim hydrating properties, cosmetic products must undergo clinical testing conducted by an independent laboratory.

These tests are carried out using an instrument called a corneometer which will measure the skin's hydration level by sending a weak electric field through the different layers of the skin.

By comparing the first measurement with the measurement after application of the product, a percentage improvement in the skin's hydration content can be calculated.

The time between two measurements varies and allows a claim like "+65% hydration after 2 hours."

The usage test

The usage test provides information about the properties of a skin care product.

It is an evaluation of the product by a selected group of users.

These tests make it possible to evaluate the sensory properties (scent, texture, comfort of use...) and the condition of the skin after use (radiance, wellness, hydration, reduction of wrinkles, dark circles...).

These results are recorded using a questionnaire that the testers fill out. This test allows statements such as: "96% of testers found their skin more radiant."

These tests can reassure you and help you in your search for a hydrating product!