Beautiful and healthy skin depends on adequate skin hydration. Skin hydration is necessary for all skin types - combination, oily, dry and normal. The question arises why normal skin type needs moisturizing, after all, it is the skin with the least flaws. Cosmetics, dry, hot weather and many factors dry out our skin, although we may not even suspect it. Moisturizing should become a necessary step in the skin routine. One of the most well-known moisturizing components is hyaluronic acid. When reading the composition of cosmetic products, hyaluronic acid can be found under various names. What is the difference between these names and which hyaluronic acid to choose to achieve the desired effect? Read all about it in this article.
A brief history of hyaluronic acid
In 1880, the first study related to hyaluronic acid was conducted. The French scientist Portes noticed that mucin from the vitreous body is different from other mucous membranes of the cornea and cartilage and called it "hyalomucin". Nevertheless, it was not until 1934 that hyaluronan was isolated by Karl Meyer and John Palmer from the vitreous of the bull's eye, but it was not until another 20 years later that its structure was described by Laurent. The first pharmaceutical degree HA in 1979. produced by Balazs, who developed an efficient method to extract and purify the polymer from rooster combs and human umbilical cords.
The importance of hyaluronic acid for the body
Hyaluronic acid (HA) is a long, non-branched polysaccharide composed of repeating disaccharides of D-glucurone and N-acetyl-D-glucosamine. Glycosaminoglycans are simply long unbranched carbohydrates or sugars called polysaccharides.
The biggest advantage of hyaluronic acid is that it holds water very well in the skin, eyes or soft tissues. A molecule of this acid can attract up to 1000 times more water than its own weight . Other areas of the body where hyaluronic acid is concentrated include tendons and joints, membranes of the eyes, synovial fluid, skeletal tissue, heart valves, lungs, aorta, and prostate.
Over the past two decades, new research has shown that the beneficial functions of hyaluronic acid include moisturizing, lubricating joints, filling the space within and between cells, creating a framework through which cells migrate, and promoting tissue and wound healing. We will distinguish and we will briefly explain the main importance of hyaluronic acid for the organism:
1. Moisturizing the skin
Skin hydration is highly dependent on HA-bound water in the dermis and epidermis, and maintenance of hydration is largely dependent on the granular layer. The amount of HA in the dermis is significantly higher than in the epidermis. HA in the dermis regulates water balance. A prominent histochemical change in aging skin is the loss of epidermal HA. Thus, the epidermis loses the key molecule responsible for binding and retaining water molecules, resulting in a loss of skin moisture. All of this contributes to the obvious dehydration, atrophy and loss of elasticity characteristic of aging skin.
Proven to reduce fine lines usually more are seen in low humidity compared to high humidity environments because they increase water evaporation from the skin.
in 2021 the study "Efficacy Evaluation of a Topical Hyaluronic Acid Serum in Facial Photoaging" was conducted. In the study, women aged 30-65 with advanced photoaging used an HA facial serum for six weeks, twice daily with sunscreen. At the sixth week, all skin properties assessed improved: smoothness (64%), plumpness (60%), hydration (63%), fine lines (31%), wrinkles (14%). The HA in the serum formula provided excellent skin hydration as demonstrated by clinical, photographic, and evaluations.
In the photo, we can see the changes in a woman's skin after using hyaluronic acid serum for 6 weeks.
Skin evaluation parameters such as smoothness, plumpness, moisture increased after the HA serum, and the brightness of wrinkles and fine lines decreased.
2. Antioxidant properties of hyaluronic acid
Oxidative stress is caused by an imbalance between the amount of reactive oxygen species (ROS) and antioxidant capacity. When in excess, ROS have damaging effects on cellular proteins, lipids, and DNA. Especially high molecular weight forms of HA are thought to be able to protect against the effects of ROS.
3. Ulcers, sunburns and wound healing
Hyaluronic acid is useful in the treatment of cold sores, mouth ulcers, wounds and burns. Many lip and oral herpes treatments contain hyaluronic acid gel, which speeds up the healing process and prevents cracking. Hyaluronic acid is present at all stages of the wound healing process, not only as a component of the wound environment, but also as a factor that actively modulates tissue regeneration. Cross-linked HA hydrogel films have been shown to accelerate full-thickness wound healing by providing a highly hydrated and non-immunogenic environment that is conducive to tissue repair.
High molecular weight hyaluronic acid molecules have been shown to have anti-inflammatory effects, while low molecular weight HA degradation products can cause inflammation.
4. Lubrication of joints
Hyaluronic acid is abundant in our body. The problem is that the production of this substance decreases with age. In fact, more than half of people over the age of 60 suffer from osteoarthritis or joint problems. The consequence of this pathology is the loss of cartilage lubrication, which gradually thins and is replaced by bone tissue, greatly limiting daily movements. Hyaluronic acid also supports movement in the sheath of connective tissue called fascia, which wraps around all muscles, bones and organs like a net.
5. Moisturization and protection of the eye mucosa
The fluid inside the eye socket (called the vitreous humor) is almost entirely made up of hyaluronic acid. Hyaluronic acid can help relieve chronic dry eyes by replenishing moisture in the eye socket, helping tear production and restoring fluid balance. Some studies show that hyaluronic acid helps inhibit the oxidative damage caused to the cornea by UVB light.
Molecular sizes of hyaluronic acid
HA can be divided into:
- High molecular weight HA (Dalton mass): > 18,00,000
- Average molecular weight HA: 10,00,000 – 18,00,000
- Low molecular weight HA: 4,00,000 - 10,0000
- Ultra low molecular weight HA: < 100,000
One such as low molecular weight hyaluronic acid (LMW-HA), also known as sodium hyaluronate, is easily absorbed and penetrates the deepest layers of the skin. This means that low molecular weight hyaluronic acid (LMW-HA) provides intensive hydration and long-lasting hydration deep into the skin. Sodium hyaluronate can plump the skin and reduce fine lines.
As the hyaluronic acid molecule increases and the molecular weight increases, hyaluronic acid remains closer to the surface of the human skin. High molecular weight hyaluronic acid (HMW-HA) provides the most visible results, but a shorter duration of effect. The results can be washed off with a simple face wash.
In what forms can hyaluronic acid be found in skin care products?
1. Raw form (INCI: Hyaluronic acid)
This compound is said to have a high molecular weight (>1800 kDa). It remains on the surface of the epidermis and creates a protective film that prevents water from evaporating. It also moisturizes the surface layers of the skin.
2. Hydrolyzed form of hyaluronic acid (INCI: Hydrolyzed hyaluronic acid)
Chemically milled hyaluronic acid, which has a low molecular weight and can penetrate deeper into the skin. It is a hydrolyzate of hyaluronic acid obtained by acid, enzyme or other hydrolysis. Hydrolysis allows the breakdown of hyaluronic acid into smaller fragments. This allows the recovery of medium molecular weight (> 1000-1800 kDa) hyaluronic acid.
3. Alkaline form (INCI: Sodium hyaluronate)
Hyaluronic acid salts are often used due to their excellent stability and ease of incorporation into cosmetic formulations. They are more resistant to oxidation than other types of hyaluronic acid. In addition, this form of hyaluronic acid has a significantly lower molecular weight than pure hyaluronic acid and hydrolyzed hyaluronic acid. It is called low molecular weight hyaluronic acid (> 100-1000 kDa). The latter penetrates deeper into the epidermis. It also strengthens and stimulates the production of hyaluronic acid produced naturally by the body, has a visible effect in reducing wrinkles and plumps the skin. However, it should be noted that hyaluronic acid salts can also be of high molecular weight.
4. Acetylated form (INCI: sodium acetylated hyaluronate)
This form of hyaluronic acid has both lipophilic and hydrophilic properties. It has excellent skin affinity and high absorption. Studies have shown that this ingredient absorbs three times more water than regular hyaluronic acid and guarantees long-lasting hydration. In addition, in 2021 researchers have shown that acetylated hyaluronic acid can inhibit the release of MMP-1, which breaks down collagen in mature skin exposed to UV rays and urban dust. Acetylated hyaluronic acid has also been shown to reduce nasolabial folds (wrinkles that extend from the nose to the mouth). Therefore, this form of hyaluronic acid is particularly promising in the fight against the signs of aging.
5. Cross-linked form (INCI: Sodium hyaluronate cross-linked polymer)
Low molecular weight hyaluronic acid salts are linked to form a higher molecular weight molecule. This compound is new to skin care. The manufacturer provides the stability of hyaluronic acid salts and the moisture-retaining properties of higher molecular weight hyaluronic acids.
Vegan hyaluronic acid
What does vegan mean in this case - is hyaluronic acid made from plants? In some places, you can find vegan hyaluronic acid extracted from wheat or sweet potatoes, even cotton, through a fermentation process. However, looking at the details of this production, this is not true. Only bacteria are involved in the fermentation process.
Hyaluronic acid exists only in mammalian tissues or in the outer wall of streptococcal bacteria. Plants cannot and do not produce hyaluronic acid.
Hyaluronic acid in the skin is not the same as sodium hyaluronate in a cosmetic formula
Hyaluronic acid in the skin is a glycosaminoglycan substance in the extracellular matrix that strongly binds water to keep the skin supple and hydrated. However, most of the hyaluronic acid in cosmetic formula is in the form of sodium hyaluronate, the sodium salt of hyaluronic acid, which has better oxidative stability and a lower molecular weight than hyaluronic acid, making it much better to use in formulas to improve penetration.
Hyaluronic acid and sodium hyaluronate applied to the skin do not reach the dermis
Regardless of size or molecular weight, any topical sodium hyaluronate or hyaluronic acid does NOT penetrate the dermis. The pathway from local application of these substances to deeper penetration is blocked in the lipid-rich granule layer. Hyaluronic acid synthesized in the skin is held back by the same lipid barrier that helps keep the skin hydrated. This means that hyaluronic acid, which the body synthesizes in the dermis, is located below the level of the granular layer to retain moisture in the skin. Above the granular layer, there is also hyaluronic acid synthesized by the body - it is easier to lose, but this form can be replaced with cosmetic products.
Hyaluronic acid supplements and their effectiveness
There is strong evidence that taking hyaluronic acid supplements has anti-aging properties that improve skin tone, hydration, and help reduce fine lines and wrinkles.
- Based on 2017 in a clinical, cosmetic, and investigative dermatology study, 60 people with wrinkles around the eyes experienced significant reductions in the depth and volume of wrinkles after 12 weeks of oral Hyaluron (a hyaluronic acid supplement). Participants also noticed skin glow and elasticity.
Evidence from other studies suggests that supplements have an effect on osteoarthritis of the knee. As for the moisturizing effect on the skin, it remains unknown without more research.
To achieve the maximum moisturizing effect, it is best to work both internally and externally. Creams, serums, moisturizing masks are used externally, and supplements are used internally, the effect of which is slower to appear, but provides a longer lasting effect. In this supplement, the main active ingredient, patented hyaluronic acid, is produced from the biological fermentation process of wheat and corn, and also uses tree sugar.
As mentioned in the article, this means that wheat is fermented with specific bacteria during fermentation.
Which serums with hyaluronic acid to choose?
Many products with hyaluronic acid can be found on the market, but although it is the same substance, as we found out, it can work differently according to its properties. The following indicators should be taken into account when choosing products with HA:
1. Most hyaluronic serums contain only 0.25-1.75% hyaluronic acid. They can be a little moisturizing skin, but will not be as effective because the concentration is too low. The percentage of hyaluronic acid to look for in a serum is just over 2%.
2. Many serums on the market only contain one form of hyaluronic acid that is suitable for the skin - it won't hurt, but it also won't help you get the full results. Instead, the best hyaluronic acid for skin will contain a mixture of three main types:
- Lighter weight molecules dive deeper, removing fine lines, wrinkles and increasing skin elasticity. These molecules help create healthy skin for a long time.
- Medium weight molecules help retain moisture and also have a longer effect.
- Larger molecules will not penetrate deep into the skin, meaning they remain on the surface of the skin. They make the skin look extremely moisturized and plump, and the outer layer of the skin retains the existing moisture for a short time and provides a more cosmetic effect.
The combination of all three of these molecular forms can give us what we really want: a strong and long-lasting moisturizing effect.
Coming to the conclusions, it can be said that hyaluronic acid is useful not only for the skin, but also for the whole body. When choosing a product, it is worth paying attention to the composition and what hyaluronic acid is included. The best option is when the product contains both high and low molecular weight hyaluronic acid. It should be remembered that a sufficient amount of water, a balanced diet and suitable ambient air have a great influence on the moisture of the skin. Even if you don't feel dry skin, you should include hyaluronic acid in your skin care routine at least a couple of times a week. The most beautiful skin is healthy, loved and cared for skin! :)
To conclude this topic, we want to share the hyaluronic acid serums that we have selected. In our opinion, these serums are worthy of attention based on their composition and hyaluronic acid.
The serum contains sodium hyaluronate. This acid will penetrate deeper into the epidermis. The effect may appear more slowly, but it will be effective and long-lasting.
An excellent choice for sensitive skin, due to the aloe vera and algae extracts in the composition, which not only soothe, but also moisturize.
A sufficient amount of ceramides in the skin improves the penetration of other, active substances into the layers of the skin.
This serum contains sodium hyaluronic acid for deeper hydration.
A big plus of this serum is that it does not contain mineral oils or synthetic fragrances.
Niacinamide, urea, panthenol, vitamin E moisturize the skin even more, together with hyaluronic acid.
Hyaluronic acid serum contains low and high molecular weight HA acids. All this provides a comprehensive effect: the high molecular weight forms a film on the surface of the skin, while the low molecular weight HA penetrates into the deeper layers, moisturizing them.
This serum stands out from the others because it contains prebiotics that help balance the microflora of the skin.
The ceramides in the composition strengthen the epidermal barrier.
This serum leaves an impressive impression due to its very broad and rich composition.
Hyaluronic acid, 4 seaweeds and 3 types of brown seaweed provide deep skin hydration.
Sphilantes (Sphilantes) in the serum mimic Botox due to their properties of relaxing facial muscles.
The serum combines five types of hyaluronic acid for extremely intensive skin hydration. Hyaluronic acids of five different molecular weights ensure extremely deep skin hydration and a strong lifting effect. As soon as you apply the serum to the skin, you get the impression that fine lines are immediately filled and the skin becomes smoother.
Using the serum for a longer period of time also improves the elasticity of the skin.
This serum is particularly noteworthy not only for its extremely strong hydration, but also for its high amount of antioxidants.
Sodium PCA (sodium pyrrolidone carboxylate) acts as a humectant in the skin.
Sodium PCA acts as an effective natural moisturizer for the skin, able to draw moisture from the air, so the top layer of the skin receives more water and the skin retains it better.
Sodium hyaluronate - penetrates deeper into the epidermis. It also strengthens and stimulates the production of hyaluronic acid produced naturally by the body, has a visible effect in reducing wrinkles and plumps the skin.
Antioxidants are also very important, which protect the skin from radical damage. These are very important substances for the skin, because free radicals are formed by various processes such as air pollution, sun, stress, environmental toxins.
The article was prepared by carolinashop.lt beautician Uršulė Grakauskaitė.