A determined woman from England claims she hasn't smiled since she was a young teenager, which she says is the only reason she's been able to prevent age-related lines and wrinkles from appearing on her face. 

"It's way more natural than Botox, and it works," says 50-year-old Tess Christian from London, England. "I don't need plastic surgery, and I don't even get facials." According to Tess, she attended a strict Catholic school growing up, and nuns were always reprimanding children for laughing, and this is how her ability to smirk instead of laugh out loud was born. Since then, she's lived a life of non-smiling, feeling like a stoic face suited her more. Because she was always acting glamorous with her poker face, she eventually was given the nickname Mona Lisa by her friends. Tess didn't smile for her wedding photos, or even when her daughter was born. By then, she was used to not smiling. But it isn't always easy. Sometimes, things are just too funny to not laugh, and she will let herself go if there's no other choice. And now, at 50 years of age, she has none of the wrinkles her friends of the same age do, thanks to her own strong will and determination.

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"What Tess does is a very effective anti-aging technique," says dermatologist Nick Lowe. But other doctors, especially ones whose specialty is mental and emotional health, think that not smiling has negative effects on a person's overall health. Tess, however, doesn't care what they think. "I'm happy; I love life," she says with a totally straight face. "I don't feel I have to walk around with a big smile on my face just to show that to people." 

Picture of Tess the proud mama and her daughter. (Tess is happy; she's just not smiling!)