Acne is a common yet complex skin condition that can be influenced by various factors, including excess oil production, bacterial overgrowth, inflammation, and hormonal imbalances. As a result, acne treatments are formulated with different active ingredients that target these underlying causes to help clear and improve the skin.
From potent retinoids that accelerate skin renewal to hydroxy acids that deeply exfoliate and unclog pores, each ingredient works in a unique way to combat breakouts and promote healthier skin. Understanding the science behind these ingredients can help you make informed decisions when choosing the right skincare products and treatments for your skin type.
In this guide, we explore the most effective acne-fighting ingredients, their benefits, and how they work to give you clearer, more balanced skin.
Retinol & Other Retinoids
Retinoids are a catch-all term for vitamin A derivatives including; retinol, retinoic acid (tretinoin), adapalene (Differin), and retinaldehyde. While retinoic acid and adapalene are usually prescription-only treatments, retinol and retinaldehyde are available in many OTC products.
The effects of retinoid treatments are dose-dependent, which means that stronger products and concentrations are more effective than weaker ones. In other words, prescription treatments are going to improve acne faster than OTC products.
The main way in which retinoids work is by increasing skin cell turnover and renewal. However, they also reduce sun damage, boost collagen production, improve the appearance of wrinkles, reduce skin pigmentation, and increase skin hydration.
Unfortunately, due to the increase in skin cell turnover, retinoids can also cause an initial ‘skin purging’ by increasing the rate that blemishes are brought to the surface of your skin. They can also cause irritation, redness, dryness, and peeling during the first few weeks of use. These initial side-effects are less likely with OTC forms of retinoids.
In addition to the above-mentioned skin benefits, retinoids can also reduce the inflammation that is associated with acne and acne scarring, and may have antioxidant and antibacterial effects. Specifically, retinaldehyde has demonstrated antibacterial effects against the p-acnes bacteria, while retinoic acid and retinol have not.
In vitro studies (i.e. studies conducted on tissue samples) have identified that retinoids may be able to reduce oil production. Unfortunately, there aren’t any clinical trials that suggest this is the case. Some studies have demonstrated that retinoids can reduce pore size and, as increased oil production is associated with larger pores, this may suggest some ability to reduce oil production.
Altogether, this suggests that retinoids can target many of the underlying causes of acne by increasing skin cell turnover, possibly reducing oil production, preventing p-acnes bacteria growth, reducing inflammation, increasing skin hydration, and by acting as an antioxidant.
Higher concentrations of retinoids have demonstrated effectiveness at treating moderate-to-severe acne but there is relatively little research regarding the effectiveness of weaker forms of retinoids such as retinol. However, retinol has been observed to cause the same cellular and molecular skin changes as lower concentrations of tretinoin and is more easily absorbed into the skin.
Research suggests that a topical combination of retinaldehyde and glycolic acid can significantly reduce the number of acne lesions after one month of use, with continued reductions after two and three months of use. In addition, this combination appears to improve acne scarring, post-inflammatory erythema (PIE), and post-inflammatory hyperpigmentation (PIH).
Overall, topical retinoids have been shown to reduce the number of inflammatory and non-inflammatory acne lesions by 40-70%.
Hydroxy Acids (AHA & BHA)
There are three main types of hydroxy acids – alpha-hydroxy acids (AHAs; e.g. glycolic acid, lactic acid), beta-hydroxy acids (BHAs; e.g. salicylic acid), and polyhydroxy acids (PHAs; e.g. lactobionic acid). Hydroxy acids act as chemical exfoliants by loosening the top layer of your skin and removing dead skin cells.
Glycolic acid alone as well as in combination with retinaldehyde has demonstrated an ability to improve the appearance of acne and acne scarring. This is largely down to its ability to increase skin cell turnover and, thus, prevent the blocking of your pores by dead skin cells.
In addition to increasing skin cell turnover, salicylic acid is anti-inflammatory and oil-soluble which means that it can easily penetrate your pores in order to unclog them. It does this by loosening and detaching the dead skin cells and other debris that build up within your pores. Furthermore, due to its ability to dissolve in oil, salicylic acid is easily able to penetrate your oil glands and reduce oil production.
Salicylic acid pads were shown to reduce the number of both inflammatory and non-inflammatory acne lesions when used for 12-weeks. In addition, the topical combination of salicylic acid and niacinamide is able to significantly reduce oil production and pore size after 12 weeks of use.
Lipohydroxy acid (LHA) is a form of salicylic acid that was developed by L’Oreal and is currently only found in their branded skincare products. Like salicylic acid, LHA dissolves in oil and is able to penetrate your oil glands. However, it does not penetrate your skin as easily, with one study finding that only 6% of LHA penetrated the skins barrier versus 58% of salicylic acid.
LHA is both anti-inflammatory and antibacterial and has demonstrated an ability to improve acne in a number of studies, with one study finding that LHA was as effective at treating acne as benzoyl peroxide.
Niacinamide
Niacinamide is a water-soluble form of vitamin B3 that can increase collagen levels, shrink pores, improve skin hydration, and reduce redness and pigmentation. In addition, it has antioxidant and anti-inflammatory effects, and can reduce oil production. In fact, a moisturizer containing 2% niacinamide was able to reduce the rate of oil production after 2-6 weeks of use.
The topical application of niacinamide can lead to significant reductions in both inflammatory and non-inflammatory acne lesions when used over an 8-week period. In addition, it has been shown to be more effective at improving the appearance of acne than a commonly used topical antibiotic (clindamycin), although there appears to be no added benefit in using the two treatments together.
Azelaic acid
Azelaic acid is a naturally occurring dicarboxylic acid that is often used to treat melasma and other pigmentation disorders. It is often used to treat acne as it is both an anti-inflammatory and antimicrobial, and is particularly effective against the p-acnes bacteria.
Some research has found that azelaic acid is as effective as benzoyl peroxide, tretinoin, a topical antibiotic (erythromycin), and an oral antibiotic (tetracycline) at treating mild-to-moderate acne. While other research found that the combination of benzoyl peroxide and a topical antibiotic (clindamycin) offered superior improvements in mild-to-moderate acne.
Azelaic acid may be an ideal treatment option if you experience both active acne and post-inflammatory hyperpigmentation as it is an effective ingredient for both conditions.
Vitamin C
Vitamin C is an antioxidant that is essential for overall skin health, wound healing, and collagen production. However, only a small amount of vitamin C consumed through diet becomes available to your skin which means that topical application is required to maintain sufficient levels of vitamin C in the skin.
While there isn’t a huge amount of research that specifically looks at how effective topical vitamin C is at treating acne, it is a potent anti-inflammatory and some research suggests that blood levels of vitamin C are lower in those with acne.
One form of vitamin C, sodium ascorbyl phosphate (SAP), has demonstrated an ability to reduce inflammatory acne lesions by 49% after 8-weeks of use and the number of acne lesions in 61-71% of individuals after 12-weeks of use.
Vitamin E
Vitamin E is an oil-soluble antioxidant that is found at high levels in oil and oil-rich areas (e.g. the upper layers of facial skin). If too much oil is produced by the oil glands, the levels of vitamin E can decrease and lead to an increase in oxidative stress and inflammation.
Like vitamin C, blood levels of vitamin E have been found to be lower in those with acne, and even lower still in the case of severe acne. Although there isn’t much research investigating the effect of topical vitamin E on acne-prone skin, one study did find that the addition of vitamin E to a treatment regimen of benzoyl peroxide and salicylic acid reduced the number of acne lesions in as little as 2-weeks.
Green Tea (EGCG)
Topical green tea appears to have beneficial effects on a variety of skin conditions which are largely due to the antioxidant molecules (polyphenols) present in green tea. These polyphenols have demonstrated an ability to regulate inflammatory pathways in the skin. The main polyphenol in green tea is EGCG (epigallocatechin-3-gallate) which seems to be responsible for green teas anti-inflammatory and antioxidant effects.
Some research has demonstrated that a topical green tea lotion can reduce oil-production by 60% after 8-weeks of use. In addition, topical ECGC can improve the overall appearance of acne by reducing inflammation and inflammatory acne lesions by up to 89% and non-inflammatory acne lesions by up to 79%.
In other research, a green tea extract was able to reduce blackheads by 61% and pustules by 28% but had no effect on smaller non-inflammatory spots. This suggests that green tea may not be an effective treatment for all types of acne.
However, as EGCG reduces inflammation, oil production, and some research suggests it prevents p-acnes bacteria growth, it is likely to be a good candidate for improving acne.
Centella Asiatica
Centella Asiatica (Cica) is a tropical medicinal plant that is native to Southeast Asia. It has been used for centuries to improve wound healing and treat a number of different skin conditions. This is due to the composition of Cica, which contains a number of beneficial saponins (asiaticoside, Asiatic acid, madecassoside, and madasiatic acid) as well as fatty acids, flavonoids, vitamin B & C, and amino acids.
Some research has suggested that Centella Asiatica can improve overall acne severity, reduce oil production, and prevent acne-related scarring. In addition, it appears to be effective at reducing certain strains of bacteria and has excellent anti-inflammatory effect.
As mentioned earlier, acne has also been linked to reduced skin hydration, reduced antioxidant levels (especially levels of vitamin C & E), and a higher skin surface pH. The twice-daily application of a Centella Asiatica extract has demonstrated an ability to increase skin hydration and reduce the skin’s pH level, as well as increase the levels of antioxidants in the skin. Specifically, the extract was able to increase vitamin C levels by 36% and vitamin E levels by 77% after 7-days of use.
Tea Tree Oil
Tea tree oil has been used medicinally for decades due to its antibacterial and antifungal properties. In addition, research suggests that tea tree oil acts as an anti-inflammatory.
In one study, a 5% tea tree oil gel was 3.5 times more effective at reducing the total number of acne lesions and 5.75 times more effective at reducing overall acne severity than a placebo over a 6-week period. In fact, tea tree oil has demonstrated a similar effectiveness to benzoyl peroxide for the treatment of acne but takes longer to see results.
Other research found that a topical combination of tea tree oil, propolis, and aloe vera was more effective at reducing the number of acne lesions, as well as the overall severity of acne and red scarring than a commonly used antibiotic cream.
A downside to the use of tea tree oil for acne is that it can cause skin irritation and allergic reactions. However, the research appears to be conflicting regarding this.
Conclusion
Understanding the different ingredients in acne treatments can help you make informed choices about your skincare routine. From retinoids that boost skin cell turnover to hydroxy acids that exfoliate and unclog pores, each ingredient plays a unique role in combating breakouts. Whether you’re looking to reduce oil production, soothe inflammation, or target acne scars, selecting the right combination of active ingredients can significantly improve your skin’s health and appearance. However, consistency and patience are key, as most treatments take time to show visible results.
While skincare products play a crucial role in managing acne, professional treatments can enhance and accelerate your results. At MEOD Beauty & Aesthetics, we offer expert facial services designed to deeply cleanse, exfoliate, and nourish your skin while targeting acne concerns effectively.
Book a facial treatment with us today and take the next step towards achieving clear, radiant skin! 🌿✨
