Red Algae Benefits for the Skin.

Red algae or Rhodophytes are marine algae mainly found in Europe (Atlantic Ocean, English Channel, North Sea). A sulfur polysaccharide is extracted from these species, which is used to thicken formulas and give them a jelly-like consistency, the carrageenan.

This biopolymer is widespread in cosmetics as well as in the food industry. Traditionally extracted from the species Chondrus crispus (also known as Irish moss), carrageenan is nowadays mainly extracted from the species Kappaphycus alvarezii, Eucheuma denticulatum or Furcellaria lumbricalis, which are very widespread in Scandinavian waters.

First, the carrageenan extracted from red algae has excellent humectant properties, allowing to retain water in the superficial layers of the skin, and thus decreasing the insensible water loss. Also called trans-epidermal water loss, this natural physiological phenomenon is due to the difference in osmotic pressure between the different layers of the skin and the surrounding air. To compensate for this, hydration is essential for all skin types. When hydrating the skin well with a carrageenan care, it is possible to avoid feelings of tuggings which go hand in hand with a cutaneous dryness or fine lines of dehydration.

Furthermore, the red algae extract is able to stimulate the synthesis of hyaluronic acid in the epidermis. As a reminder, hyaluronic acid is a biomolecule that ensures the hydration of the skin and gives it a plumped-up appearance. Over the years, its content decreases and its quality also changes. Every decade, we lose about 6% of hyaluronic acid. This drastic drop leads to an atrophy of the fatty pockets located in the depths of the dermis, which is the cause of the appearance of wrinkles and fine lines on the skin's surface. Even though hyaluronic acid is present in greater quantities in the dermis, its synthesis rate is higher in the epidermis than in the dermis. Thus, by stimulating its epidermal synthesis, red algae benefits the preservation of a rebounded skin as long as possible.

Moreover, the extract of red algae promotes the limitation of imperfections on the surface of the skin. Indeed, studies have demonstrated the bactericidal activity of carrageenan towards Staphylococcus epidermidis and Enterococcus faecalis, two microorganisms involved in the development of acne and its associated inflammatory reactions.

Finally, red algae extract stimulates the synthesis of ceramides, which reinforces the waterproofing of the epidermis and limits insensible water loss. As a reminder, ceramides are lipids organized in dense and structured lamellae that form the intercellular cement.