Pimples and Acne: Effective Ingredients To Fight Them

According to S.F.D. (Société Française de Dermatologie), acne affects 15 million people in France. This skin disease can appear on the face as well as on certain parts of the body (chest, back, buttocks, etc.). Acne is the most common reason to see a dermatologist and can lead to a lack of self-confidence and psychological problems.

This chronic inflammatory disease originates in the hair follicles: The sebaceous glands secrete too much or too thick sebum, causing the openings to become blocked. This is known as dysseborrhea. In this greasy environment, a bacterium that normally occurs only in small amounts on the skin can multiply. This bacterium is called Cutibacterium acnes, which triggers an inflammatory reaction on the surface of the skin.

Several factors favor acne outbreaks: stress, pollution, hormonal fluctuations, poor lifestyle (lack of sleep, smoking, unbalanced diet, lack of hygiene...).

• Hydroxy acids:

Hydroxy acids are a large family of molecules. This family includes the alpha-hydroxy acids (A.H.A.), the beta-hydroxy acids (B.H.A.) and the poly-hydroxy acids (P.H.A.). These are different, but all effective against acne.

1. A.H.A:

AHAs usually come from fruits, which is why they are also called "fruit acids". The molecules of this family have many benefits for the skin, but it is their keratolytic action that gives them a great effect against acne. Through their keratolytic action, AHAs remove dead skin cells from the skin's surface by weakening the lipid bonds between the cells. This gradually removes clogging of the pores and allows the sebaceous glands to work better.

AHAs provide an important molecule used in cosmetics, glycolic acid. In addition to keratolytic properties, this active ingredient also has sebum-regulating properties that are very useful in the treatment of acne. Glycolic acid fights the accumulation of sebum in the dilated pores of the skin, which leads to the formation of acne lesions. Glycolic acid, which is known as the smallest of all AHAs, can easily be absorbed into the layers of the skin. Thus, it works not only on the surface, but also in depth.

Studies have shown that glycolic acid has an interesting bactericidal effect even in an environment with an acidic pH of 3 to 4.5, and even at low concentrations (<10%). Thus, it can inhibit the proliferation of Cutibacterium acnes on the skin of patients with acne vulgaris, in particular by affecting the stability of the cell membrane of the bacterium.

Lactic acid is another A.H.A. commonly used in cosmetics. Lactic acid is milder compared to other AHAs. In general, it is recommended for those with sensitive skin seeking gentle exfoliation. Because this molecule is larger than glycolic acid, it enters less deeply into the epidermis and is therefore less irritating than glycolic acid. Lactic acid is thus an excellent alternative for skin that has not tolerated glycolic acid products. However, it has the same keratolytic properties as glycolic acid, making it effective against acne.

1. B.H.A.:

The main molecule in the B.H.A. family is salicylic acid. This active ingredient has several characteristics that qualify it to fight acne.

Salicylic acid activates skin regeneration. Thanks to its keratolytic properties, it removes dead skin cells from the skin surface and inhibits clogging of pores. As a result, it effectively fights the appearance of blackheads and refines pores, providing a radiant and even skin.

Note: Salicylic acid has a high affinity for sebum and therefore enters deep into the pores of the skin.

The surface of the epidermis can be colonized by harmful microorganisms that unbalance the microbiota and cause redness, irritation or pimples. Sometimes they can be painful. Thanks to its antiseptic properties, salicylic acid prevents the growth and proliferation of bad bacteria such as Cutibacterium acnes, a microorganism that causes the inflammatory reactions in acne.

Skin with acne is often a source of discomfort. The pimples can cause tingling, itching and burning. The soothing properties of salicylic acid relieve the symptoms associated with inflammation. In fact, salicylic acid intervenes in the arachidonic acid cascade and inhibits the synthesis of prostaglandin E2, molecules that cause inflammatory and painful effects. In the treatment of acne, it thus soothes the painful pimples and visibly reduces redness.

1. P.H.A.:

Considered the new generation of A.H.A., they are known for their keratolytic action, which means they remove dead cells (desquamation process), boosting cell renewal. This desquamation deeply cleanses the pores, reducing the appearance of skin impurities.

PHAs also have moisturizing benefits. This is due to the numerous hydroxyl functions (OH-) they contain in their chemical structure. These bind water molecules and thus prevent transepidermal dehydration, strengthening the skin barrier.

Unlike A.H.A. and B.H.A., P.H.A.s suit all skin types, including sensitive skin. This is because their high molecular weight allows them to remain on the surface of the epidermis. This explains their good skin tolerance compared to other acids, which are absorbed deeper into the skin.

There are many different P.H.A., but gluconolactone and lactobionic acid are the most commonly used.

When they are in contact with the skin, PHAs have a keratolytic effect by removing dead skin cells from the skin's surface and opening the pores. As a result, sebum is better distributed on the skin surface. This allows Cutibacterium acnes to replicate less, which in turn reduces the appearance of pimples.

In addition, PHAs have moisturizing and hydrating properties. Contrary to popular belief, skin hydration is also crucial for acne prone skin. It prevents transepidermal dehydration and restores the skin barrier to protect the skin from external aggressors and soothe the skin.

The use of P.H.A. in acne-prone skin is interesting because they act gently against impurities and respect the skin barrier.

• Retinol:

Retinol (a vitamin A derivative) is an active ingredient that was long disliked due to its irritating and dehydrating potential on the epidermis. Today, however, it is subject to legal regulation and is increasingly used in cosmetics, mainly because of its excellent action against the signs of skin aging, but also against acne.

Like hydroxy acids, retinol has a keratolytic effect and removes dead skin cells on the surface of the skin. Pores are opened, and the skin texture is refined, preventing the appearance of blackheads and/or comedones.

• Bakuchiol:

In 2007, bakuchiol was first used in cosmetics. Several studies have defined it as a natural alternative to retinol, which is why it is also called "bio-retinol" or "phyto-retinol". Bakuchiol allows to effectively fight the signs of aging and acne without the side effects of retinol (irritation, stability problems, photosensitivity, etc.).

Studies have been looking at the broad anti-acne effects of Bakuchiol for about ten years. It acts on multiple levels.

Bakuchiol is an anti-inflammatory agent. Inflammation is another issue of skin affected by acne. Unfortunately, there are few ways to directly relieve the inflammation associated with acne. However, studies show that bakuchiol has a strong inhibitory effect against COX-2, an enzyme involved in the formation of prostaglandins.

Bakuchiol fights the Cutibacterium acnes bacterium responsible for acne. A study proves that bakuchiol has an excellent inhibitory effect on C.acnes and is also very effective in inhibiting other microorganisms such as Staphylococcus and Candida.

Bakuchiol is a sebum-regulating agent. Excess sebum clogs the pores of the skin, allowing bacteria to grow, leading to inflammation, infection and visible acne. Bakuchiol works by reducing the secretion and thus the activity of an enzyme called 5-α-reductase. This converts testosterone to DHT, which binds to the androgen receptors of the sebaceous glands and causes excessive sebum production.

Bakuchiol accelerates wound healing. Acne skin has been shown to contain a higher level of matrix metalloproteases (MMPs) than so-called normal skin. These enzymes (mainly collagenase and elastase) break down the matrix in the acne lesion, slowing the healing of acne-affected skin. Topically applied, Bakuchiol inhibits the activity of these enzymes and prevents them from interfering with the healing of micro-injuries left by acne pimples.

• Zinc:

Zinc is a trace element that is essential for the body. It is found in meat as well as in some plants after fermentation. A zinc deficiency would increase inflammatory symptoms. Zinc is contained in various forms in skin care products, e.g. as zinc oxide, zinc gluconate or also as zinc PCA.

Zinc PCA is a sebum-regulating agent that regulates sebum production and thus prevents skin impurities. It is also known that Zinc PCA limits the development of microorganisms such as Cutibacterium acnes. This bacterium is found in excess in acne-prone skin.  

Thus, zinc PCA reduces inflammation, regulates sebum production and restricts bacterial growth.

• Azelaic acid:

Azelaic acid occurs naturally in some grains such as barley and is one of the dicarboxylic acids. It is found in medications used to treat acne and is applied topically in concentrations between 15 and 20%. In cosmetics, creams and serums rarely contain more than 10%. However, even in this concentration, the broad action against skin blemishes is significant. It acts on several levels:

It regulates keratinization. Keratinization or cell differentiation is a maturation process of epithelial cells that become loaded with keratin and eventually become dead cells that form the stratum corneum. Azelaic acid normalizes this process, resulting in smoother skin and preventing dead cells from clogging pores, thus preventing the formation of blackheads and comedones.

It fights bacteria. Thanks to its antibacterial properties, azelaic acid limits the proliferation of P. acnes and S. epidermidis bacteria, which are responsible for the inflammatory reactions in acne. In addition, it acts specifically on these two microorganisms, but has no negative effects on the "good bacteria" on the skin.

It limits inflammation. Azelaic acid reduces redness as well as the marks left by skin blemishes – this is called post-inflammatory erythema. For example, studies have shown that azelaic acid inhibits the release of pro-inflammatory cytokines such as the interleukins IL-1β and IL-6 and the factor TNF-α. In addition, another study indicated that azelaic acid promoted the regulation of kallikrein-5 in epidermal keratinocytes, which in turn lowered cathelicidins, reducing inflammatory processes.

• Niacinamide:

Niacinamide is a water-soluble derivative of vitamin B3. It is essential for your body's proper functioning, as it is involved in the production of NAD and NADP, coenzymes known as energy transfer molecules. This vitamin has numerous benefits for the skin. It protects the skin from free radicals produced by sun rays, tobacco and pollution. Niacinamide also regulates sebum production, inhibits the proliferation of bacteria such as C. Acnes and stimulates collagen synthesis. In addition, it is a stable antioxidant that tolerates both light and heat very well.

Niacinamide is a comprehensive anti-pimple active ingredient that acts before pimples appear, but also afterward to soften possible marks and scars.

First of all, this vitamin regulates the sebum content on the skin surface, preventing the clogging of pores that cause blackheads and comedones. In addition, it has an antibacterial effect and fights microorganisms such as P. acnes, which are responsible for the inflammatory reactions in acne;

Its soothing properties help reduce inflammation, thus reducing the redness associated with blemishes.