I was three years younger than a famous teen model when I devoured her biography. She was THE “It girl,” and she was a teenager, like me. So when she declared eating 1,000 calories of M&Ms is the same as eating 1,000 calories of any other food, we were willing to believe her. There were so many too-good-to-be-true revelations then. Remember this one: Home perms don’t damage your hair.

So, yes, I wish I knew then what I know now.

Most of these “life lessons” were harmless. And whenever common sense failed me, science usually came to the rescue and I made course corrections.

But there was one lesson I learned too late. It was so important I was determined that my daughters and other girls would not repeat that same mistake. I had just turned 29. I was a new mom and our daughter, Willa, was at home with a sitter while I was sitting in a packed hospital waiting room. People with puffy white bandages covering an ear, part of a nose, or a cheek surrounded me. I was the next patient whose face would be cut to remove a skin cancer. How did this happen to me? How did the girl with the Mediterranean complexion, who tanned so easily and who “treated” breakouts by drying them in the sun get in this situation? How could I have been so wrong?

It began when I discovered a pimple under my eye. It morphed into a scab that would bleed every time I washed my face. Eventually, I went to a dermatologist who wasted no time referring me to a MOHS surgeon. Until that moment I had never heard the term “MOHS.” But I learned MOHS is the most effective surgery for removing basal cell cancers like mine. Apparently mine was deep, which meant the surgeon had to go through four layers of tissue to remove all the cancer cells.

Every year there are more new cases of skin cancer than there are of all cancers combined: More skin cancer cases than breast cancer or prostate, lung and colon cancers combined. What’s more, the incidence of people under 30 developing melanoma is increasing at a faster rate than any other age group. Many people have a genetic predisposition for melanoma. But studies also show a clear cause-and-effect relationship between exposure to the sun and skin cancer.

Yes, I wish I knew then what I know now.

I also wish I knew that every day I was out in the sun without sunscreen I was causing premature aging of my skin. Vanity was – and continues to be – a powerful motivator for good behavior.

After my MOHS surgery I resolved to get serious about taking care of my skin. But every dermatologist I saw said the same thing: “Christy, what is going on with your skin is a direct result of what you did or didn’t do when you were younger. The fact is fully 80% of lasting skin damage happens by age 18.” So while it may be too late for me – for so many of us Moms – to get it right… for our young daughters, healthy skin is all about prevention – and starting young.

We don’t wait for our kids to get a cavity before we get them to brush their teeth. So why would we wait for them to get a breakout or a sunburn for them to start taking care of their skin? After all, it’s our largest organ.

So when Willa was 8 and showing signs she was ready to start taking ownership of her skin, I was shocked to find there were virtually no natural skincare products formulated for girls. We looked everywhere: Mass drugstores, high end apothecaries and department stores. We found nothing but pink bubblegum-scented chemical formulations made in China.

So we started “willa.” It took us four years of development before we had it right and were ready to introduce willa natural skincare products. The first year we spent talking to girls and their moms in focus groups. We knew how important it was to understand girls’ behavior – or lack of behavior – when it came to taking care of their skin. We wanted to know why a girl doesn’t like to wash her face – or why she resists sunscreen (especially when her mom slathers it on.)

We learned: “I don’t like sunscreen because it is sticky and makes me look like a ghost.” So we made sure our formulations went on dry and added a slight tint to offset the super white of zinc oxide and titanium dioxide. Girls told us they don’t like to moisturize their skin because they are afraid it will clog their pores and make their face look greasy. So we developed an oil-free moisturizer that goes on clear without a shine. I knew that if I wanted Willa and other girls to take ownership of their skin, they needed to love the way the products look, smell and feel. They had to love using the products because no amount of nagging ever created a healthy habit.

Today our 7-year-old, Julia, now puts on willa sunscreen on rainy days in November. And we hear every day from girls all over the country how much they love using willa. That’s our big secret. At willa, we make great natural skincare products girls actually want to use, so they can make a habit of taking care of themselves. Now girls have not only the knowledge, but also the tools to have a different skincare story than their mothers.

Also read what Marta wished she had known in her youth.