Cate Blanchett recently got a facial with costar Sandra Bullock that they nicknamed the "penis facial."

The treatment, officially called the Hollywood EGF facial, uses progenitor cells of the human fibroblast taken from Korean newborn baby foreskin.

The reasoning behind this wacky trend is that adding stem cells to the dermal layer rejuvenates skin because it is effectively introducing new tissue.

The weird beauty practices of the Hollywood elite have become so bizarre they sound like parodies of themselves. Think bird poo and placenta facials, snake venom eye cream, and being stung by bees. Yet, the latest trend manages to take things one step further. Cate Blanchett credits her youthful glow to a treatment that uses the foreskins of Korean newborn babies. Aka, a penis facial.

"[We] saw this facialist in New York, Georgia Louise, and she gives what we call the penis facial," Blanchett told Vogue Australia. "It’s something – I don’t know what it is, or whether it’s just cause it smells a bit like sperm – there’s some enzyme in it so Sandy refers to it as the penis facial."

The Sandy she refers to here is her" Ocean’s 8" co-star Sandra Bullock, a woman not new to the world of unusual anti-aging treatments. After all, she regularly applies hemorrhoid cream to her under eye area to reduce puffiness.

But back to the penis facial. What exactly does this special treatment involve?

Well, first of all, it’s not really called a “penis facial”. On the company website, it goes by a far more palatable name: the Hollywood EGF facial. It involves a cleanse, an intensive TCA peel, micro-needling, an electrifying mask, and, finally, FDA-approved Epidermal Growth Factor (EGF) serum.

“EGF is derived from the progenitor cells of the human fibroblast taken from Korean newborn baby foreskin – which helps to generate collagen and elastin,” Louise explains. So the EGF used in the treatment comes from skin cells produced in a lab.

“FDA approved stem cells and peptides are penetrated deep into the skin using a special electric micro-needling wand. This process allows the active ingredients to be transported deep in the skin by creating temporary micro-channel.”

It all sounds very sciencey, but how effective is it really?

Stem cell use is fairly widespread in the cosmetic industry. However, it is usually in cream form and the cells have less icky origins – they tend to be plant-based. The theory goes that adding stem cells to the dermal layer rejuvenates skin because it is effectively introducing new tissue, thus making one's complexion appear younger. The process is also thought to release chemicals that aid aging cells, again, making them appear younger.

Studies have shown that stem cells can repair damaged tissue – for example, wounds and burns – but it is not so clear how effective they are as a radiance-boosting treatment. Blanchett's post-facial glow could have just as much, or perhaps more, to do with the chemical peel, the electrifying mask, and the peptides.

Anyway, with a two-year waiting list and each session costing $650 a pop, you probably couldn’t get an appointment even if you wanted to.

IFLScience has reached out to stem cell experts to clarify the benefits and risks of stem cell facial treatments.

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