Fermented skincare
14 August 2024
SKII’s skincare products worth its price? As one of the biggest names in the Japanese beauty scene, SKII has cemented its status as one of the top luxury brands in Asia for its skincare products. Since the release of its award winning Facial Treatment Essence in 1980, SKII has been a hit; and continues to remain a fixture on many best selling skincare guides. The miracle ingredient in SKII’s products,Pitera, is proprietary to the brand and is often mentioned in commercials and the media. However, very little is known about this elusive ingredient; giving it an air of mystery and secrecy. In this review, I’ll be discussing the studies on Pitera and share my review of SKII’s skincare.
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The hero ingredient in SK-II’s Facial Treatment Essence is the Pitera extract. Although widely marketed as Pitera, the active ingredient is Galactomyces ferment filtrate, a type of postbiotic. Galactomyces Ferment Filtrate is a byproduct of yeast fermentation of presumably, rice, which forms sake.
Introduced in 1980, SKII’s Facial Treatment Essence remains one of J-beauty’s top selling products. According to SKII, the Facial Treatment Essence contains 90% Pitera, an ingredient that is proprietary to SKII. Pitera is derived from yeast fermentation of rice and includes more than 50 micronutrients, including vitamins, minerals and amino acids.
The famed story goes, the idea that yeast could offer anti-aging benefits came to SK-II researchers, who, in the 1970’s, noticed that the hands of elderly sake brewers looked younger than their chronological age. The researchers postulated that the fermented sake mixture that the sake brewers were soaking their hands in for several hours a day contributed to the youthful appearance of the brewers’ hands. After 5 years of research, involving studies on 350 yeast strains, Pitera was discovered.
Pitera is a proprietary ingredient of SKII, which is owned by US consumer care conglomerate, Procter and Gamble. This means that Pitera is only exclusively available to SKII; and dupes by other brands do not contain the same ingredient. Pitera’s exclusiveness to SKII also shrouds it in secrecy about the substrate used for fermentation (it has never been publicly mentioned; but we’ve been made to assume it comes from rice because of the brandstory of its origins that harps on sake, which is derived from rice) and exact micronutrients that make up Pitera- although the brand does share that it’s a mixture of some amino acids, acids, vitamins and minerals.
The ingredient list of SKII’s products reveals that Pitera is Galactomyces Ferment Filtrate. This means that Pitera, is postbiotic (i.e. a by-product of fermentation by a yeast strain known as Galactomyces). Since the ingredient list explicitly states “filtrate”; this means that mixture of presumably, fermented rice (that forms sake) and Galactomyces yeast strain has been filtered to leave behind the clear, watery liquid that has made its way into the Facial Treatment Essence. The Galactomyces yeast strain has been filtered out; so no worries about yeast propagation in SKII’s skincare.
Also according to SKII, Pitera offers a slew of benefits to the skin- pigmentation busting, antioxidant protection, reduces oiliness and shrinks pores. The evidence that the company provides on the website to back up these claims, is however, lacking. Nonetheless, making Pitera the signature ingredient of SKII’s skincare has worked well for the brand; and the facial treatment essence has stayed unchanged for 4 decades.
These are the results of published studies and trials conducted by P&G (SK-II’s parent company) on Pitera; as well as my critique on these studies:
• In November 2022, a trial involving 20 women in Japan showed that the use of a moisturiser containing Pitera for 2 weeks reduced changes in pore size, transepidermal water loss and redness induced by 2 weeks of wearing face masks1. This study, however, did not contain any controls– so would these changes from mask wearing naturally reverted back in the absence of mask wearing? Did the other ingredients in the moisturiser also contribute to this result? This study also did not assess long term outcomes.
• A June 2021 study led by the same researchers found that 4 weeks use of Pitera skincare reduced the daily fluctuation of pore size, redness and roughness in Japanese women aged 22 to 34 years old2. In this study, the researchers found that the subjects’ pore sizes looked larger in the morning after waking up and they postulated that this was due to retention of sebum and dehydration of the skin. After using Pitera skincare, subjects noticed that this change was reduced. The clinical significance of fluctuations and reducing pore size in the morning is unclear. This study did not quantify changes in pore size over the period of study, so we cannot say for certain whether Pitera reduces pore size. Another limitation of this study was the lack of controls; which also leads one to question whether a non-Pitera skincare routine would have also removed sebum build up (like a regular facial cleanser) and hydrate the skin (like a regular moisturiser) to give the same results.
In vitro studies:
• In human skin models, galactomyces ferment filtrate increased the expression of caspase-14, an enzyme involved in the formation of the stratum corneum3. However, the exact role of caspase-14 maintaining the skin barrier function is unclear.
• Another study involving human cells showed that galactomyces ferment filtrate activates aryl-hydrocarbon (AhC) receptors and the expression of filaggrin (FLG) and loricrin (LOR) genes44. Cell studies showed that galactomyces ferment filtrate has anti-inflammatory benefits by potentiating the expression of genes with anti-inflammatory effects such as cytokine IL-37; and by downregulating the expression of genes with inflammatory effects such as CXCL14 and IL6R genes5.
Although these cell studies showed that galactomyces ferment filtrate/ Pitera could enhance the expression of genes and differentiation of proteins related to skin barrier function and protection against inflammation; the clinical significance remains unclear, because the molecular effects of galactomyces ferment filtrate are not fully understood6. Put simply, these molecular changes caused by galactomyces ferment filtrate in petri dishes of skin cells; may not translate to the same molecular changes when Pitera is applied to the skin. More importantly, skin barrier integrity and function is due to a composite of factors such as pH and lipid barrier. The clinical significance or the impact that Pitera has on gene transcription remains unclear.
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I was very excited to put in words my thoughts and experience with using SK-II for this blogpost. I began my first foray into skincare in my early 20’s with SK-II’s Facial Treatment Essence from 2008 to 2011. I started with using SK-II’s Facial Treatment Essence before progressing to using the entire range- the facial wash, moisturiser (SkinPower cream), eye cream and the occasional face mask.
The good about SK-II’s Facial Treatment Essence
In the years that I used SK-II’s Facial Treatment Essence, I felt that my skin was more supple, moisturised and radiant. What made me switch my entire skincare range to SK-II then was the compliments I received from my skin when I first started using SK-II Facial Treatment Essence. Despite my tiredness from long working hours, friends and colleagues complimented me for having glowing skin. Back then, I attributed these compliments to my switch to SK-II’s products.
SK-II’s Facial Treatment Essence has a very thin, watery consistency. It’s meant to be used as a toner, before serums and moisturiser are applied. Although the consistency is very thin, SK-II was moisturising enough for me, even when I skipped using moisturiser and serums. This can be attributed by the humectants in SK-II Facial Treatment Essence- Butylene glycol and pentylene glycol.
The Bad about SK-II’s Facial Treatment Essence
The first thing that accosts your senses when using SK-II Facial Treatment Essence is its smell. The sour smell associated with fermentation is striking, although the scent disappears in minutes.
As a luxury brand, skincare products from SK-II are expectedly costly. A 160ml of SK-II Facial Treatment Essence will set you back SGD$239; and the 80ml of the Skinpower Cream costs $245 from Sephora Singapore. Although I received compliments about my skin looking glowing, I did not see noticeable improvements in skin texture, fine wrinkles or pore size despite using SK-II exclusively in my earlier years. At this price point; I found it hard to justify continuing to use SK-II when there are more affordable skincare products with evidence-based active ingredients for reducing hyperpigmentation and reducing signs of ageing such as retinoids available in Singapore.
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Even though SK-II has published sponsored in-vitro studies and clinical trials (see above), the methodologies employed were lacking in controls, long term outcomes and endpoints that were clinically relevant (reduction pore size fluctuation in the day is very different from a reduction in actual pore size). This is not to say that Pitera or Galactomyces Ferment Filtrate does not work- it’s just unclear. The marketing of SK-II’s Pitera has been so powerful and effective, but as a doctor that practises with an empirical, evidence based, it’s was hard for me to justify continuing to splurge on Pitera instead of using efficacious and efficacious skincare ingredients such as vitamin C.
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Pitera/ Galactomyces Ferment Filtrate may offer some skin brightening benefits; but the evidence and data that support its benefits on the skin barrier or improving signs of ageing are considered nascent for now. The products from SK-II are very expensive; and in my opinion; there are more efficacious and affordable products out there that can strengthen the skin barrier and reduce signs of ageing such as hyperpigmentation and fine lines.
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References:
1. Enhanced Fluctuations in Facial Pore Size, Redness, and TEWL Caused by Mask Usage Are Normalized by the Application of a Moisturizer. Miyamoto et al. J Clin Med. 2022 Apr; 11(8): 2121.
2. Daily Fluctuation of Facial Pore Area, Roughness and Redness among Young Japanese Women; Beneficial Effects of Galactomyces Ferment Filtrate Containing Antioxidative Skin Care Formula. Miyamoto et al. J Clin Med. 2021 Jun; 10(11): 2502.
3. Human keratinocyte caspase-14 expression is altered in human epidermal 3D models by dexamethasone and by natural products used in cosmetics. Kataoka et al. Arch Dermatol Res. 2013 Oct;305(8):683-9.
4. Galactomyces fermentation filtrate prevents T helper 2-mediated reduction of filaggrin in an aryl hydrocarbon receptor-dependent manner. Takei et al. Clin Exp Dermatol. 2015 Oct;40(7):786-93.
5. Galactomyces Ferment Filtrate Potentiates an Anti-Inflammaging System in Keratinocytes. Yan et al. J Clin Med. 2022 Oct 27;11(21):6338.
6. Transcriptomic Analysis of Human Keratinocytes Treated with Galactomyces Ferment Filtrate, a Beneficial Cosmetic Ingredient. Nakajima et al. J Clin Med. 2022 Aug; 11(16): 4645.
