Christie Brinkley Feels ‘Strong’ at 69: ‘The Number Doesn’t Match My Spirit’ (Exclusive)

Christie Brinkley knows one thing: there is no age limit to feeling great and looking good. In fact, at 69, the supermodel is feeling as sprightly as ever. 

“I pretty much feel, as I'm approaching 70, the same way that I felt when I was approaching 30. I feel good. I feel strong,” Brinkley tells PEOPLE while hosting Pet Life Unlimited’s Furever Young senior dog adoption event at the Animal Haven shelter in New York City on May 23. 

“I feel like the number doesn't match my spirit, so I may as well just keep spiriting on,” she added. 

Next February, Brinkley will reach what she considers a “milestone” age — “I think they all signal to us certain things,” she explains.

Stepping into each stage of her life has come with an element of surprise. "I've been shocked by not feeling the way I thought I was supposed to be feeling at that age," she further notes.

But worrying about her digits isn’t her top priority. “I don't believe that focusing on age is going to make you feel any better about it. I think curiosity in the world around you and just wanting to do something with each day, that is what keeps you young and going,” she says. 

So do the simple things in life. “I just love any time I have any family and friends around, just being able to sit and laugh — I think laughter heals everything,” she says. 

What also goes a long way is a good hair day, which Brinkley feels is the “foundation” for any glow-up — humans and senior dogs alike. 

The mom of four (which includes her pup Chester) actually teamed up with Pet Life Unlimited to help groom a bunch of fostered senior dogs into tip-top shape to increase their chances of finding a new home.

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Brinkley even transformed a few of them into fabulous stars of her pup photo shoot, directed by the model herself and inspired by a selection of her iconic magazine covers over the past few decades, including her 2014 PEOPLE cover.

“I think I'm the right age. I can relate,” she tells PEOPLE of why partnering with the pet brand on the cause felt like the right opportunity. “Senior dogs, more than anybody, need to be loved and they don't ask for much.” 

If there’s one characteristic Brinkley is most known for, it’s her blonde locks. Though, in March, she was seen embracing her gray roots on Instagram. "The second you see gray hair, it raises the question, just like when you cut bangs ..to keep or not to keep?" she wrote. 

She’s since dyed her roots back to blonde but has a piece of advice for other women deciding to let their grays show. 

"I think the important thing is to do what works best for you. People will put pressure on you in every direction,” Brinkley tells PEOPLE. 

As empowering as it is to rep what isn’t the beauty standard, going gray can be a double-edged sword. “If you don't go gray, some people really make a big deal about it, like ‘Oh, that's so disappointing. She's not owning it. She's trying to do something other than who she is.’ And it's like, no. I believe firmly that if there's something bothering you, take care of it," Brinkley encourages.