What 17 celebrities do to look much younger than their age

It's easy to write off celebrity agelessness as the result of pure luck in the genetics department. But that wouldn't be totally accurate: Scientists say that up to 40% of the physical changes that make us look older are caused by non-genetic factors.

That means seemingly immortal stars must have a few anti-aging tricks that actually work.

Yes, celebrities have lots of disposable income, professional makeup artists, and Photoshop to aid them — but we pored through dozens of interviews and found that lots of them claim to preserve their youthful glow using simple, evidence-backed health habits. (In other words: Get ready to hear a lot about sleep, exercise, and sunscreen.)

Here are some totally doable anti-aging strategies from 17 famous folks who never seem to look older. 

Pharrell Williams has the world's simplest skincare routine.

In a 2014 interview with Time Out London, Williams asserted that he's definitely not a vampire, finally addressing the (half-joking) speculations of fans looking to explain his perpetually youthful appearance. 

"I'm willing to go on record as saying that I don’t drink people's blood," he said. "How do I stay so young-looking for a 40-year-old? I wash my face."

It's probably safe to say there are also some really good genes at play.

Victoria Beckham eats salmon — every single day.

Beckham revealed her dermatologist's perfect-skin advice during an interview with Net-a-Porter last year.

"I see a dermatologist in LA, called Dr Harold Lancer, who is incredible. I've known him for years — he sorted my skin out,"she said. "I used to have really problematic skin and he said to me, 'You have to eat salmon every single day.' I said, 'Really, every day?' And he said, 'Yes; breakfast, lunch or dinner, you have to eat it every single day.'"

It's not exactly clear what Beckham means by "problematic skin" (acne? rosacea? psoriasis? eczema?) so it's hard to say whether her dermatologist's advice is sound. But the fats found in fish do have anti-inflammatory effects in the body. Some research suggests they could help protect the skin against sun damage, too — but definitely don't use salmon as a substitute for sunscreen.

Jared Leto is a vegetarian who never skimps on sleep.

"It's probably just down to sleep and diet,"Leto told GQ in 2013, when asked how he looks like he's still in his 30s. "If you travel long haul a lot or don't sleep much, it's not going to last very long, that's for sure."

And for what's worth: small of handful of studies has shown that sleep deprivation can make people look older.

Leto also noted he's been on a vegan/vegetarian diet for about 20 years. It's an eating pattern that — done right — is linked to lots of health benefits.