Of all the luxury products out there, few have had the longevity (and endorsement of Oscar-winning beauties, like Cate Blanchett) of SK-II. But do the ingredients – and the scientific research behind the ingredients – measure up to the price of the line, which can cost hundreds of dollars for a single product?
The Main Ingredient: Pitera – A Fermentation Product of Yeast
Under conditions of low oxygenation, anaerobic organisms are able to produce energy via a process known as fermentation. While many skin care formulations include by-products of fermentation, Pitera is different because it “[…] uses an exclusive yeast while other skincare brands are based on yeast from beer,” according to Takashi Yoshii, senior manager for Global Technical Marketing at the Procter & Gamble Kobe Technical Center.
Unfortunately, with all due respect, little research thus far demonstrates that different sources of yeast make a difference in the quality of fermentative by-products. (For the record, Pitera is from Saccharomycopsis, which is from the same family as Saccharomyces cerevisiae and uvarum used in beer.)
Fortunately, there is research demonstrating that yeast is an excellent source of peptides, proteins, amino acids, carbohydrates and nucleic acids, as documented in the journal Household and Personal Products Industry. Although some of these compounds merely hydrate the skin when applied, they are still most likely beneficial for the skin, if for no other reason than moisturization.
There is also limited research, produced by Procter & Gamble (the brand behind SK-II) attesting that the Pitera increases the production of hyaluronan – a component found in the skin’s extracellular matrix – in a synthetic skin model. Since hyaluronan synthesis normally slows with age, this is considered to be a unique way to address the problem of aging.
Does Pitera Work in Other Ways as Well?
Another exciting report from Procter & Gamble is that Pitera (Saccharomycopsis Yeast Ferment Filtrate) reduces production of oxidative species.
Yeast fermentation has been shown to increase the activity of components of the skin known as polygalacturonases. One common polygalacturonase in skin care is allantoin, which is normally soothing for the skin. So perhaps Pitera’s soothing properties stem from increased allantoin production.
Use of the Line
From inspection, my favorite product in the line is the SK-II Facial Treatment Essence ($137.99, Amazon.com) which seems to contain the highest concentration of Saccharomycopsis Yeast Ferment Filtrate (Pitera), as well as sodium hyaluronate.
Sodium hyaluronate, often used in place of its hyaluronic acid form for its greater stability in skin care products, acts as a natural moisturizing factor, drawing water into the skin. This has two immediate effects: one, it minimizes trans-epidermal water loss (TEWL), and two, it creates a slight swelling of the skin, which reduces the appearance of fine lines and wrinkles a bit. This means that sodium hyaluronate may have long-term effects as well: according to Dr. Howard Murad, hydration of the skin with NMFs allows the skin to operate at optimum capacity, and provides a better defense against environmental assaults.
In short, I like the SK-II line, particularly the SK-II Facial Treatment Essence. I think that the research suggests yeast extract may be beneficial, and the sodium hyaluronate is proven to beautify and hydrate the skin.
What I wish for: more research (especially if it could be, say, a double-blinded in vivo comparison study validating Pitera’s efficacy), more comparison studies (tell me exactly why I should use this yeast when there are retinoids and antioxidants and peptides like palmitoyl pentapeptide-4 with numerous studies backing them out there!), and a lower price tag.
Of course, as-is, the products look lovely and feel luxurious – and make a wonderful gift for that beauty junkie in your life! I personally am sticking to my antioxidants/retinoids/niacinamide/super high-SPF ritual until more research on Saccharomycopsis is released, but in the meantime, I don’t see how these products could hurt. (Unless, of course, you don’t like parabens; SK-II Facial Treatment Essence has methylparaben).
As always, talk to your dermatologist before trying this or any new product. Product Rating: 8/10 (High concentration of proven effective ingredients: 2.5/3, with a deduction for a relatively small amount of published research for Pitera. Unique formulation: 3/3. Value for the money: 1.5/3. Sunscreen [available in some of the SK-II line, though not the SK-II Facial Treatment Essence]: 1/1).
Ingredients in SK-II Facial Treatment Essence
Water, Saccharomycopsis Ferment Filtrate, Sodium Hyaluronate, Butylene GlycoI, Cellulose Gum, Polysorbate 20, Glycerin, Methylparaben, Sodium