Growing up in Korea, I was surrounded by seas of lotions, creams and moisturizers everywhere I went—I never second-guessed the importance of skincare. But, despite the craze today around the 10-step Korean skincare routine, the obsession with applying topical product after product, and all the different ingredients popping up (from snail oil to gold-infused creme), the only Korean skincare ritual that my family passed down to me is the one spoken about the least: the Korean diet.

For those who aren't familiar, Korean cuisine is always a balanced meal of grilled protein and rice (never bread), with lots of various fermented vegetables such as kimchi and miso paste.

Kimchi, a fermented, pickled cabbage almost iconic in our culture, is dense with minerals, vitamins A, B and C, fat-free and most importantly, loaded with probiotics, a gut-friendly bacteria that takes shelter in your stomach after ingestion. And what probiotics do for our health and our skin, is almost immeasurable: our stomach, the so-called “second brain,” is actually the ruler of our overall health. And when our stomach is off, our skin takes a beating almost immediately. But with probiotics, our stomach is able to fend off a lot of what causes these problems, and gets our skin to its optimal condition.

What's more, Koreans consume a lot of collagen-based dishes and soups. Think of collagen as the gatekeeper of moisture in our cells, a "wall" to keep our cells hydrated so they don't lose structure or lead to weaker, stretchier, and thinner skin i.e. wrinkles, fine lines, dry skin, cellulite, and the loss of structure in your hair follicles (integral to holding on to your hair). Ingesting collagen facilitates new regeneration of skin, muscle, bones and joint cells, which is something my mother and grandmother never let me forget if I ever decided to be picky with my food.

At this point, most of us know that what we put into our body directly translates to how we look and feel. But I do think that most of us either like to conveniently forget, or underestimate just how much what you ingest, translates to your skin. If you take a second to trace some of our most frustrating skin and hair problems to their roots, you would find yourself circling back to your stomach and liver, two of our most stressed out, hungover organs.

Despite being entrenched in this Korean skincare diet, I didn’t always put two and two together. I always ignored the immediate link between pizza date-nights to morning after pimples, and rarely thought about eating the “right” type of foods. I focused mostly on putting extra eye cream on nights following a tough day, and religiously spent hundreds of dollars monthly on massages, facials, and more and more products.

The realization of just how important diet is to the health of my skin actually only occurred to me one day in my early twenties when I got burned from hot oil. I turned to silicone patches, topical creams and ointments to ensure that my skin would heal but saw little improvement.

So, I decided to try making my treatment an inside job and started taking 20 grams of collagen every day, hoping for its regenerative and healing benefits. Sure, I hated the taste of it, but I stuck to it. Though it should never become the only path to healing skin, in my personal experience, I started noticing a dramatic change not just on my arms, face and hair a month after I started my daily intake. My eyelashes, brows and hair got so much thicker, and my skin, once chronically dry, didn't need as much topical attention as it used to, 10-Step Korean skincare routine, or otherwise.

And that was when it hit me. Our moms were right all along—when it comes to skincare, it really is what’s underneath, and inside, that counts.

Sally Kim is the founder of the collagen and probiotics powder Crushed Tonic.

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