Victoria Beckham celebrated her fortieth birthday today, and she still looks as amazing as she did during her Posh Spice days. What’s her secret to looking so young? Her skin, of course.

E! News exclusively learned from the fashionista that her beautiful skin is in its current state with the help of her dermatologist, Dr. Lancer, so they went straight to the source to find out her secrets.

"The skin's condition is improved through a simple three-step approach of exfoliating, cleansing, then nourishing," Lancer said. "Exfoliation stimulates natural protein production in the upper layer of the dermis, increases oxygen flow and encourages enzyme protein production in the stratum cornea—the deepest layer of skin—which triggers self-repair."

The three-step process stimulates cell production and collagen production, which results in younger looking skin.

The doctor also revealed that Victoria is very diligent in wearing SPF to protect her gorgeous skin. She uses his Lancer Sheer Fluid Sun Shield SPF 30, which doesn’t leave a greasy residue.

That sunscreen came in handy when she spent her big birthday on a luxury resort close to the Grand Canyon in Utah, according to Daily Mail. She spent the time hiking with her husband, soccer player David Beckham, and their four children, Brooklyn, Romeo, Cruz and Harper.

Images via Twitter/Victoria Beckham