“I’m six feet, one-and-a-half inches—at least, last time I checked. I live in my ballet flats because they don’t add any height. Flat-footed, I’m not taller than my boyfriend, but with heels, absolutely—and he’s about 6’3. Dance was always my thing growing up, and I think that’s why I treat myself more as an athlete than just a model. I love to challenge myself physically and mentally.

But I’m not a professional athlete, I’m not a professional dancer, I’m not a professional anything; I have never considered modeling an actual job title. I have yet to determine what my job actually is but, yeah, modeling is a fun and funny gig.

Sure, I’ve had to make choices between my body and my optimal healthy look, starting a career at 15 in an industry where, as a model, my body is a part of my business. And from 15 to 21, naturally everybody changes. I’ve had to find a happy point of where I feel best and also can do my job.

I am aware that I am part of an image that other young girls see and I want to be proud of that, even though there is this double standard of being healthy and what that actually means in my industry. But I feel healthiest and most beautiful when I take care of myself in everything from what’s on my top shelf in my bathroom to eating well and doing exercise.

Maybe it’s my background in dance, but I feel most beautiful when I feel strong. My body is strong. To me, beauty is so much more about how you feel than products, and that comes down to what you’re putting in your body and how you take care of yourself. And I’ve learned that more about health and nutrition than I did when I was starting out. At age 15, 16, 17, traveling all the time, I could eat whatever I wanted and I was a stick, a twig. I wasn’t conscious about what I was eating, it was just not part of my educational upbringing in the Midwest. That was something I really learned in moving to New York, being in this city where there are so many alternative options, so many kind of foods.

As I’ve gotten—I hate to say it—older, or, as time goes on, my body responds differently and I’ve learned so much about how to take care of myself. Nutrition-wise, I think the ‘aha moment’ was when I even changed my baking. When I was 18, I stopped dancing as much as I had been, and my body started to change, and I was just eating whatever, not really thinking about it. I would always make my Gram’s butter-and-sugar, normal chocolate-chip cookies. But then I got on a health kick, and I got really big into trying different kinds of exercises, I hired a trainer, Justin Gelband, and I try to do something every day, even if it’s just stretching or a one-mile run. A body in motion stays in motion.

I’m also constantly trying different ingredients in the kitchen, or thinking about what I’m putting in or on my body. I love to try new beauty products that are cleaner, more natural, or organic alternatives that I was never exposed to growing up. Like coconut water—there wasn’t much of it in St. Louis. When my parents used to see it in the fridge they’d be like, ‘What is this gross stuff?’ It’s hysterical, my dad loves it now, but my family used to come over and I remember one time, my aunt tried the Juice Press I had and was like, ‘This is terrible! Karlie, what are you doing to yourself?!’ But being conscious of all of that, I feel different, I feel completely different.

For food, I think everything in moderation, and variety is key. It’s the same thing with products. For example, I just tried this new shampoo by Living Proof and it makes my hair bounce differently. I think it’s a combination of both switching up what you’re using and the specific product. I see the same thing with exercise: when I switch up exercises, I feel and see a difference in my body.

In terms of my beauty routine, when I’m getting ready in the morning, less is more; it’s about how quickly I can get out the door, which is why I like Laura Mercier Tinted Moisturizer in Bisque. I like using tinted moisturizer because it doesn’t clog pores. It combines a great moisturizer with that velvety ‘veil’ you want that doesn’t look too cakey or too covered-up. And then I use a bit of RMS Un Cover-Up in 22. My skin is very dry, so oily products are never a problem, and what I like about Un Cover-Up is that I can use it here on a pimple but also to take my lip color down a little on shoots or whenever. I have really red, bright lips and I like to mute it sometimes. This has a good texture and it has a bit of green in it, which cuts the red down but not in a drastic way that makes it look crazy, like I have no lips.

I love a cream blush because the powder alternative is too messy and it takes up too much room in my carry-on to bring a brush, and a bronzer, and a powder blush, so I always use the Laura Mercier Cream Cheek Color. It’s dewy, and I love the fact that it’s not really red. It’s that kind of '90s look that’s all about dewy and really gorgeous skin and building up from there. I like the Givenchy Mister Light for under the eyes. I like really creamy, dewy stuff. For mascara, I use either L’Oréal's Voluminous Million Lashes or Marc Jacobs’. I like his because it’s a gel and has a big fat brush, so it applies smoothly—none of that clumpy stuff.

In general, though, I work with the best hair and makeup artists in the world, so I don’t try to pretend that I’m an expert. I like to just take care of my skin and create a great foundation for these artists to transform me into whatever character on the shoot. I like to use Caudalie Gentle Cleanser with my Clarisonic to wash my face and Bioderma Crealine to take off makeup.

I just found this one moisturizer that I really like: Earth Tu Face Hydrate + Repair. It’s kind of waxy, but it’s really hydrating and is probably injected with coconut oil. I love all oils, coconut, olive—I actually use olive oil on my skin weirdly enough. I like taking a basic cream, like Embryolisse, and mixing in a drop of the Decléor Neroli serum or Rodin oil. Especially in the winter, my skin gets really dry so I do whatever I can to moisturize. And for lip balm, I love Bag Balm because it does the trick but it doesn’t smell good, I’ll tell you that. [Laughs]

When I started doing research into nail care and nail polish, I found out that being ‘five free’ is really important—it means the product doesn’t have the unhealthy additives. Deborah Lippmann’s are ‘five free,’ but that also means eliminating a lot of the ingredients that make the polish harden, shine, etc. It’s a lot like baking gluten-free and vegan things. It’s creating the same delicious end-product—great nail polish—but without the easy go-to chemicals, or the butter, sugar, eggs, and dairy. Weird metaphor, but Deborah’s ‘five free’ mission was when I first became interested in finding other products that share that same clean—or clean er—message. I like Tatcha’s products, the Ren Gylcol Lactic Radiance Renewal Mask, and Harry’s razors, the ones made for guys since they don’t have women’s versions yet.

I’m super simple with my hair but I do love Harry Josh’s new line of tools, the dryer and his new straightener, too. My hair grows really slowly, so I’m not trying to do anything intentional to it, but it’s taking forever to grow out. Right now, I’m liking the Après Beach Wave and Shine Spray by Oribe, and also the Bob Recine hair oil, which gives shine but doesn’t make it droop.

Otherwise, Source Naturals Liquid Melatonin is really, really good. It’s a homeopathic solution to help you sleep. I’m knocked out in like 10 minutes; it’s really potent stuff, so it’s the last thing I’ll do before going to bed.

What else…I kind of fell off the Invisalign bandwagon and didn’t complete my first round so I had to do it again; this is Invisalign: Round Two. But the next time I do an Into The Gloss interview, hopefully I will be done.”

—as told to ITG

Karlie Kloss photographed by Emily Weiss in New York on March 18, 2014.