"I'm actually enjoying the sleepless nights because it's bonding with my little girl," Mendes, who is slowing starting to return to the spotlight following the birth of her daughter, reveals.
However, in spite of her hands-on approach to parenting, the 41-year-star says she hasn't "earned the right" to dish out mothering advice.
"I want to respect all the moms out there. They're going to be like, ‘You know what? You're a few months in. Just shut up."
Although Mendes is clearly loving life as a new mom, the actress still takes time for herself to ensure her mental and physical well-being.
"I realized a long time ago that I needed to have some kind of routine," she shares of her fitness plan, which includes running and interval sprints. "I don't love it, but I've made peace with that."
Mendes also lifts weights but "nothing too heavy, because my muscle bulks up pretty easily. I mix it up with yoga, or sometimes I'll hike with my trainer."
As for her everyday diet?
"I haven't eaten meat in about six years, because I don't agree with factory farming here," she shares. "This is just what worked for me, it's important to say, but when I cut that out I immediately felt better. And also, after a year of eliminating it, my skin looked brighter and healthier overall."
When it comes to her mental health, Mendes is a firm believer in therapy. "Having [a therapist] who's totally objective and who points out my patterns— I find that really helpful," she admits. "And I'm lucky to work with someone who doesn't just sit there and nod her head, you know? I need to hear what you think! Tell me what's wrong with me so I can fix it!"
The Hitch beauty, meanwhile, has yet to share a glimpse of her daughter, and she and Gosling have gone to great lengths to protect their bundle of joy from the paparazzi.
"I believe there is a public self and a private self," the fiercely private actress shares. "My sisters and my good friends are experiencing that now [with] Facebook and Instagram. When they freak out about a friend of theirs posting a bad picture of them, I'm like, ‘Well, imagine how I feel! Get used to it!'"
Thankfully, Mendes has the unwavering support of her family and her partner to help her stay sane in Hollywood.
"I've had the same girlfriends since I was 12, and I've made amazing girlfriends since," she says. "And my mom and my two older sisters have always been there telling me I could accomplish anything. We have each other's' backs in the best way."