Some of our favorite stars have clearly stumbled upon the fountain of youth. How else do you explain the fact that they seemingly don't age? Styles may change, but celebs like Jennifer Lopez, Rob Lowe and Kate Hudson inexplicably look the same today as they did a decade (or more!) ago. Keep reading to check out more of Hollywood's ageless wonders, starting with Rachel Bilson. This actress -- who turns 35 on Aug. 25, 2016 -- shot to fame in 2003 when she landed the role of lovable Summer Roberts on "The O.C." She's been in Hollywood now for more than a decade, yet the mother of one looks like she's hardly aged a day.
Jennifer Lopez has been in the biz for nearly three decades, but you'd never know it based on her looks! The 47-year-old stunner looks like she's barely aged a day since her famous Versace Grammy ensemble in 2000. Give us all your secrets, girlfriend!
Jaclyn Smith has aged gracefully! The former "Charlie's Angel" star, 70, looked ageless while doing some shopping in March 2016 compared to the promo shot from the show from 40 years ago.
Former supermodel Christie Brinkley may not have stayed Billy Joel's "Uptown Girl" forever, but she sure has retained her girlish looks since the '80s. This gorgeous lady turned 62 in 2016!
Gabrielle Union could still pass for a high school student even though her cheerleading days are long behind her. Whatever beauty routine this 43-year-old actress is following, bring it on!
We finally figured out why Pharrell Williams is so "Happy." It's because he doesn't age. Seriously, check out the 43-year-old producer in 2005 -- and now.
Will Smith may be the movie king as far as Hollywood is concerned. But as far as we're concerned, the 47-year-old actor will always be the Fresh Prince of Bel-Air -- because he looks like he's barely aged since the show went off the air in '96.
The only thing that's changed about 48-year-old Julia Roberts in the past 15 years is her hair.
If you really want to be our "Hero," Enrique Iglesias, you'll explain to us how you're 41 and haven't aged in the past decade.
LL Cool J has given up on over-the-top fashion since the early '90s, but the 48-year-old hasn't given up on looking like he's in his 20s.
Eva Mendes just keeps getting better with age! The 42-year-old beauty looks even better now than she did back in 2004.
Have mercy! If this is what 53 is supposed to look like, we're all in trouble. Thanks a lot, John Stamos.
Kate Hudson's passion for plunging necklines isn't the only thing that's gone unchanged since 2003. She may favor more dramatic makeup these days, but her face looks just as youthful as ever.
Yep, Stacey Dash was almost 30 when she starred as Dionne in "Clueless." The 49-year-old actress is clearly the most stunning freak of nature ever.
The boyishly good-looking "Revenge" star is 44 years old! It must be the blond hair and baby blues that make Gabriel Mann look so young.
Two things haven't changed for 59-year-old Vanna White since 1983: her ability to turn letters like a pro on "Wheel of Fortune" and her youthful appearance.
The 47-year-old actress is like a fine wine! She just gets hotter and hotter with age. We wonder what Lucy Liu's secret is...
Tobey Maguire's facial hair may make him look a few years older, but as long as he keeps rocking the same hairstyle he sported back in '02, he'll look more like a Spider-Boy than Spider-Man -- even though he's 41 now!
Michelle Williams may have starred in "Dawson's Creek" more than a decade ago, but to us, she'll always be Jen Lindley -- mostly because she looks exactly the same now at age 35 as she did when the show ended.
Much like the elf she played in the "Lord of the Rings" trilogy, Liv Tyler is immortal and impervious to aging. She's the youngest-looking 39-year-old we've ever seen!
How do we explain 47-year-old Edward Norton's ageless appearance? Well, the first rule of being a vampire is you do not talk about being a vampire. The second rule of being a vampire is...
When she got her start in Hollywood, Reese Witherspoon was a cherub-faced beauty. Decades later, nothing has really changed -- and she turned 40 this year!
At 39, Alicia Silverstone is clearly anything but "Clueless" when it comes to making herself look as fresh-faced now as she did back in 1997.
Patrick Dempsey thankfully ditched the unruly 'do he favored in the mid '90s. Other than that, he looks practically the same -- if not better! -- at age 50 than he did in his 20s.
Can you believe Ralph Macchio is 54?! His youthful looks are pretty shocking -- especially when you do the math and realize that when he made "The Karate Kid," Ralph wasn't a kid at all! The '80s star was already in his 20s when he took on the star-making role.
Did a glitch in the matrix give Keanu Reeves the ability to look young forever? The actor is 51!
Michelle Pfeiffer has played everything from a high school student to a high school teacher -- and she's kept her youthful looks all the while. Could you have guessed she's 58?
You'd think that years of hard rockin' would have aged Jon Bon Jovi. Not so! He's still looking young and fresh at 54.
Scott Wolf, 47, hasn't seen much success on the small screen since his "Party of Five" days, but hey, at least he's still got his boyish Bailey Salinger looks!
It's hard to believe the 44-year-old Oscar winner has been alive for more than four decades. Jared Leto barely looks a day older than when he first burst onto the scene in the mid-'90s.
Thanks to her forever-young face, Naomi Campbell has been one of fashion's top models since the mid-'90s. Even today, the 46-year-old beauty barely looks a day over 30.
Technically, we watched Elijah Wood grow up in the spotlight -- but we're using the term "grow up" lightly. The 35-year-old has had the same baby face for years!
Paul Rudd played Cher's college-age stepbrother in "Clueless." Somehow, he still looks like he could fit in on campus -- even though he's 47 now.
She may be a 46-year-old mother of three, but Gwen Stefani still looks like she's "Just a Girl."
He's been around since the '80s -- and survived some hard living -- but Rob Lowe has maintained his youthful glow. How does the 52-year-old do it?
Elle Macpherson may be known as The Body, but you've also got to give her credit for her face. It hasn't aged a bit. And she's 52!
Jennifer Aniston has worked steadily since the late '80s, but there's not much of a difference in her appearance from 1997 to today. If only all of us could look as great as the 47-year-old "Friends" alum!
Chalk it up to her GOOP lifestyle, but there was hardly a sign of aging on Gwyneth Paltrow's face between 1997 and 2014. The 43-year-old mama is certainly genetically blessed!
Paparazzi camera flashes must have preservation powers because Tom Cruise looks just as good today as he did decades ago. Talk about a 54-year-old with good genes!
Demi Moore's marriage to Ashton Kutcher may have ended, but the 53-year-old beauty looks almost the same as she did during her days as a member of the Brat Pack.
Decades after her pageant days, Halle Berry's award-winning beauty is still perfectly intact. Isn't she flawless at 50?
Former Miss America Vanessa Williams could easily take on the pageant circuit at age 53.