Kate Upton Admits It Was 'a Little Nerve-Wracking' to Go Makeup-Free for People 's Beautiful Issue

When Kate Upton was pregnant with daughter Genevieve, now 2, she began experiencing a skin "struggle bus."

"Of course, the first bit of melasma was right over my upper lip, which made me look like I had a permanent mustache. [My skin's] reaction to being in the sun changed a lot," Upton, 28, tells PEOPLE.

So the supermodel admits that going makeup-free for PEOPLE's 2021 Beautiful Issue was "always a little nerve-wracking." But Upton says she was excited to embrace her skin just how it naturally looks.

"I feel like makeup is so nice if you use it in a way that makes you feel better about yourself. But there are also so many times when you're putting on makeup to cover up or change different ways of your face," says the star. "I see it more and more with social media. It creates a negative mental relationship with yourself that you feel you should change. So I think being makeup-free stands for loving myself how I am. Although I do love makeup, I appreciate what being makeup-free means."

While speaking with PEOPLE's podcast host and editor-at-large Janine Rubenstein for PEOPLE Every Day, Upton admitted that for her, "feeling beautiful is not a constant."

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"It's always a journey because we're human. You feel stressed some days and you feel overwhelmed or tired. I think just going back to appreciate the connections we have — the family, the friends and putting how I feel beautiful on my relationships and on my relationship with myself. [That] is how I feel most beautiful," says Upton.

Now that she lives in the Florida sunshine with her MLB star husband Justin Verlander, keeping a regimented skincare routine is more important to the model than ever before. "It's hard with the sun. I have such sensitive skin that suddenly I'm always red. So anything cooling is nice," Upton says.

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She's all about staying moisturized with hydrating creams, "lots of serums" and anything with hyaluronic acid. "I've been very into LED light masks. It's helping even my skin tone, because like I mentioned, the melasma," adds the model.

When Upton's not feeling her best, she also likes to do small skin rituals to enhance her mood.

"I love face masks because sometimes you'll see even the simple change of your complexion," she says. "I have a great ice roller that I love to use to bring down puffiness. There are little things you can do to make yourself feel more confident."

As Upton approaches her 30th birthday, which she says she still has some "mixed feelings" about, she feels happier than ever in her own skin.

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"Definitely the closer I get to 30, the more changes I see in my skin and in recovery, which adds to needing more sleep. But I also feel really happy where I am in my life," she says. "So I always try to focus on that. Not the number."