Combat ashy skin with moisturising essentials

Dry skin irritancy is a universal struggle. Nearly every person will experience it at some point in life. Exogenous factors like the weather can have an effect, but luckily there are defenses that can be used to protect against dry skin as well as proactively counteract it. Jacques Strydom, technical manager at AECI Specialty Chemicals, discusses dry skin in various skin types and how to address it with essential moisturising actives.

WINTER WITH ITS cold temperatures, low humidity, and chilling winds is normally the worst time of year for skin moisture. These environmental factors are rather effective at stripping the skin of its natural lipid barrier, which under normal circumstances would protect the skin from transepidermal water loss (TEWL). Over and above the direct effects of the weather, when it is cold, we tend to take warmer (and longer) showers or baths, once again stripping the skin’s lipid barrier with soap.

Apart from a beautiful appearance, higher levels of melanin protect skin during sun exposure. While there are many benefits to having a more melanated skin type, there are also certain drawbacks. Differences in melanin levels in turn relate to differences in sun-related skin changes, affecting the stratum corneum’s water content and its ability to retain moisture. Dry skin is also a bit more noticeable on certain skin tones, due to the direct contrast with the lighter appearance of dry and flaky skin cells.

A SOLUTION TO IMPROVE DRY SKIN

Besides the itchiness and irritancy caused by dry skin, it also makes the skin appear older. Dry skin does not necessarily cause cracks, but it does enhance the appearance thereof.

The solution? Moisturisation, of course. Luckily, moisturisation is a well-studied field of skin care and one that we know to be absolutely vital to modern skin health. Today, there are many options to promote moisturisation, including ingredient classes like emollients that form an artificial barrier to prevent moisture loss, humectants that draw moisture to the skin and which hydrate the stratum corneum, as well as actives that penetrate deeper into the skin to restore and protect important mechanisms that keep skin supple and hydrated.

EXPLORING HYALURONIC ACID

Arguably one of the most important moisturising actives is hyaluronic acid (HA). HA occurs naturally in all vertebrate tissues and throughout the body in various connective tissues, synovial joint fluids and in varying amounts in the skin. It is in the skin that the body holds the primary reservoir of HA – up to 50% of the total. Because of its unique rheological, viscoelastic and hygroscopic properties, HA plays a pivotal role in protecting, stabilising and reinforcing skin at the cellular level.

HA, along with collagen, elastin and essential lipids, form the primary elements of the human skin matrix. Native HA is naturally produced by skin cells mainly in varying concentrations of low molecular weight polymers (15kDa), all the way through to high molecular weight polymers (up to 2 000kDa). The size of the polymer dictates its biological role in the skin and its primary benefit.

When using HA in skin care, scientists prefer to work with sodium hyaluronate (or NaHA), which is the synthesised salt counterpart of HA. It has similar benefits to HA and is more stable in its form and less likely to oxidise. Sodium hyaluronate also has a smaller molecular size, so it can penetrate deeper into the skin, where it can attract and hold moisture, swell and therefore assist in making skin look plumper. This mechanism of action results in a youngerlooking skin with less visible wrinkles.

HIGH MOLECULAR WEIGHT NAHA

AECI Specialty Chemicals offers sodium hyaluronate in various formats, depending on the level of moisturisation that needs to be achieved and whether you are formulating a cleanser, lotion, cream, serum, toner or colour cosmetic product. The most common grade used in all these applications would be the crystal-clear liquid 1% solution of high molecular weight sodium hyaluronate molecules. The high molecular weight means that the ingredient will not penetrate skin very deep, but rather focus on important outer barrier protection. The following benefits can be expected from this grade:

• helps retain moisture for healthier skin

• decreases skin roughness for improved texture

• improves barrier function for decreased TEWL

• decreases desquamation for softer, smoother skin.

BALANCED MOLECULAR WEIGHT FRACTIONS

The next grade that AECI Specialty Chemicals focuses on is a balanced ratio of high, medium, and low molecular weight fractions of sodium hyaluronate, designed to target different layers of the skin from the surface through the epidermis and dermis.

This means that not only the surface of the skin will benefit, but deeper action can be expected, which assists in plumping the skin. The concept is similar to the springs of a bed’s mattress – when the springs are old and worn, it won’t help just to replace the duvet.

This grade is available in both a liquid and powder format.

PREMIUM NAHA GRADE

The final grade of sodium hyaluronate is targeted at serious skin care products, which call for supercharged moisturisation. With the INCI listing Water, 1,2 Hexanediol and Sodium Hyaluronate, this ingredient is an optimised ratio of seven unique molecular weights ranging from 3 000 to 2 300 000Da. The seven different molecular weights ensure:

• maximum moisturisation is provided to skin

• multi-functional benefits are attained after a single application

• that with continuous application, theingredient can stimulate skin to producemore HA for deeper moisturisation andyounger-looking skin.

This premium NaHA grade provides shorttermand long-term benefits. Immediatelyperceivable, the medium and highmolecular weight molecules remain onskin’s surface and create a lubricious andprotective film to reduce water loss andenhance skin’s barrier function, protectingit from dehydration. In the long term, thelow molecular weight molecules penetratethe epidermis and after continuous use,they ensure moisturisation of the deeperlayers of the epidermis. These moleculeswill also stimulate skin’s ability toproduce HA and act as a water reservoir,attracting and binding to water, ultimatelymaintaining optimal moisturisation,elasticity and firmness – preserving skin’syouth from within. •

AECI Specialty Chemicals – jacques.strydom@aeciworld.com or thureya.sarlie@aeciworld.com