Hyaluronic Acid (HA) is a natural glycosaminoglycan found in the body's connective tissue. HA exists in both the epidermis and dermis, responsible for keeping the skin plump and hydrated.

One of the first signs of HA depletion that you can easily feel is when the uppermost layer of the skin (the epidermis) gradually becomes drier and rougher as we age. HA is also an essential component of the extracellular matrix (ECM) which provides structure and volume to the skin. HA's natural function in the skin is to fill the spaces between cells and prevent collagen and elastin fibers from collapsing.

However, the available HA concentration in the skin begins to decrease in the 20s and accelerates from the 40s onwards. This can be due to both natural aging (intrinsic aging) and external environmental factors (extrinsic aging) such as UV radiation. Damage to collagen and elastin fibers in the dermis (solar elastosis – degeneration of elastin fibers due to prolonged sun exposure) leads to a loss of skin elasticity. 

Low HA content can lead to dry skin, wrinkle formation, decreased skin firmness, and uneven skin texture. Fortunately, topical HA application can offer many benefits, including addressing the aforementioned skin conditions while keeping the skin barrier functioning optimally.

Mechanism of Action of Hyaluronic Acid

HA is a natural humectant with hydrophilic properties that acts like a sponge, capable of holding up to 1000 times its own weight in water. This helps reduce or slow down the rate of transepidermal water loss (the phenomenon of water in the skin evaporating through the epidermis into the surrounding environment), keeping the skin hydrated, thereby making it less sensitive and less irritated.

HA in various forms can be injected into the skin as a filler – also known as cross-linked Hyaluronic Acid. Meanwhile, topical HA is often formulated as a serum or cream with precise molecular sizes and concentrations – which is particularly important for HA to be absorbed through the stratum corneum, penetrate the epidermis, and reach deeper into the innermost layer of the skin – the dermis.

HA comes in various forms with different molecular weights, some residing in the epidermis and others in the dermis. The lower the molecular weight, the deeper HA can penetrate. Some product formulations combine different molecular forms of HA, including:

• Whole HA: has the largest molecular weight, so it cannot penetrate deep into the skin and mainly stays on the epidermis, helping to lock in moisture and naturally hydrate the skin.

• Fragmented HA: has a smaller molecular weight than whole HA, so it can penetrate deeper into the skin, providing more optimal moisturizing effects.

• Encapsulated HA: has the smallest molecular weight, capable of penetrating deep into the basal epidermis, thereby nourishing, hydrating, and supporting repair of damage.

These active ingredients have been shown to provide immediate and lasting hydration to the skin, as well as help improve the appearance of mild to moderate sun-induced aging signs.

Clinical studies have also shown that HA helps support wound healing. Additionally, combining HA-containing serums or creams with Retinol in skin treatment yields excellent results, especially for dehydrated or sensitive skin, helping to reduce the risk of skin irritation.

Overall, Hyaluronic Acid is a versatile skincare ingredient, suitable for all ages and skin types – from dry, dehydrated, aging, sensitive skin, and rosacea-prone skin to oily, acne-prone skin, all can benefit from various product formulations containing HA.

Key benefits of Hyaluronic Acid for the skin:

• Boosts skin hydration

• Improves skin barrier function

• Enhances skin elasticity

• Plumps the skin, reduces wrinkles/fine lines

• Smooths skin texture, provides a radiant, natural glow

• Reduces transepidermal water loss

• Gives skin a youthful appearance

oh!oh! HA serum: amber - Hyaluronic Acid Serum for Hydration, Brightening, and Wrinkle Prevention

oh!oh! HA serum: amber is an excellent recommendation for those looking for a suitable Hyaluronic Acid serum. This is an entirely new product line from oh!oh! - a Korean cosmetics brand specializing in providing beauty and skin health solutions, designed to meet the continuous changes in the environment and consumer preferences.

The product formula includes a blend of rich moisturizing ingredients Sodium Hyaluronate + Rose of Jericho that can quickly and deeply penetrate the skin, providing instant and long-lasting hydration. At the same time, the combination of Niacinamide and Allantoin will help soothe, brighten, and strengthen the skin barrier, preventing wrinkle formation, and leaving the skin firm, smooth, and supple. The serum has a rich yet lightweight texture, providing a refreshing sensation immediately after application.