There are so many anti-aging products on the market that one of the best and most efficient ways to narrow your focus (in the opinion of this beauty editor) is to filter by ingredient. That being said, some of the best ingredients are under-the-radar and yet to be household names, like CoQ10 and epidermal growth factor (EGF) — the latter of which is the main ingredient in the serum that Grey's Anatomy and Emily in Paris actress Kate Walsh told People "has magical powers."

If you haven't heard of it, you're not alone — even as someone deeply immersed in the world of skincare ingredients, I only caught wind of it in May of last year. EGF is an anti-aging ingredient claiming space on the shelves of stores and medicine cabinets alike.

Dr. Brian Hibler, MD, board-certified dermatologist at Schweiger Dermatology Group, gave us a quick(ish) explanation of what you need to know about the very scientific-sounding ingredient. Like collagen and CoQ10, EGF is a naturally existing molecule in your skin that decreases as you age. "EGF is a protein that's involved in different cell signaling pathways. Upon binding [with another cell] EGF can tell a cell it should grow, divide, or produce certain proteins," Hibler told InStyle. Basically, EGF cells have the important task of communicating what and where in your epidermis needs to be healed and rejuvenated. It's like a project manager that gives every individual their specific instructions for a successful outcome.

Shop now: $169; dermstore.com and nordstrom.com

Bioeffect is an entire skincare brand with EGF starring as the hero ingredient. It's also the serum that received glowing praise from Walsh for making her skin thicker and thereby stronger, reducing the appearance of wrinkles, and improving the density of collagen, elastin, and lipids.

The serum is able to do all that because, as Dr. Hilber explains it, "EGF is a single molecule that can stimulate multiple positive effects on the skin, namely increased collagen, skin thickness, and hyaluronic acid production. Some studies also show that it improves hyperpigmentation."

So when Walsh says the Plumping and Firming Serum has "magical powers", she's hardly exaggerating. Why look for a product (or multiple!) that have collagen, hyaluronic acid, and vitamin C as active ingredients when you could simplify it down to one ingredient? We know $169 is a high price to pay for a serum, but the science indicates that epidermal growth factor does so much, it's worth it. You can find Kate Walsh's "magical" Bioeffect EGF Plumping and Firming Serum at Dermstore and Nordstrom.