Bizarre teen trends have been horrifying parents for generations, but health officials are warning that a vampire-inspired biting fad could be dangerous, not to mention disgusting.

Teenagers obsessed with the “Twilight” vampire saga, or those simply fascinated with fangs, reportedly have been biting each other -- hard – and then licking or sucking the blood.

“These are kids who think they are real vampires,” said Dr. Orly Avitzur, the medical advisor to Consumers Union, the agency that publishes Consumer Reports magazine.

Avitzur said conversations with teens and sessions spent trolling vampire-related teen Web sites convinced her that the trend was taking hold. Indeed, groups like “I drink blood,” a category at www.experienceproject.com, and “I want to be a vampire” at the site www.43things.com are filled with apparent posts from young people with a yearning for blood.

“Having that thick, warm copper-tasting blood in my mouth is the best thing I can think of!” wrote a teenager identified as “GothicGirl10” this year. “Sometimes my boyfriend lets me feed off him. I let him feed off me as well.”

Such talk alarms medical experts, who warn about the dangers of blood-borne diseases such as hepatitis and HIV, as well as the risk of nasty infections. Typically, 10 to 15 percent of human bites wounds become infected.

“If you break the skin, your mouth is pretty dirty,” said Dr. Thomas Abshire, a pediatric blood and cancer specialist and spokesman for the American Academy of Pediatrics. “The human mouth flora is dirtier than a dog or cat’s.”

Equally worrisome is the motive behind the acts, the idea of branding or owning another person, the experts said.

“If you think about it, there is such glamorization in those teen vampire movies, they make it seem so sexy and appealing and intriguing,” Avitzur said. “It’s all mixed up with passion.”

But at least one teen who likes to bite says adults have got it all wrong. Michael Kaplor, 16, of Dallas, says he was biting his girlfriend intermittently for more than a year because the intimacy of it, not for any gothic obsession.

“It’s really gotten a bad rap because of this whole vampire thing,” said Kaplor.

In reality, he said, a lot of teens bite – and leave marks – for the thrill of it.

“You feel it for a considerable amount of time afterwards,” he said. “It’s the way you receive happiness.”

Some people do draw blood, but that’s where Kaplor draws the line.

“Kids don’t understand how dangerous blood is,” the high-schooler said, “especially if it’s not your own blood.”

Do you know teens who’ve turned vampire obsession into a real-life drama? Tell us here.

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Attaining an even, all-over tan is a futile effort, no matter how much you sunbathe buck naked. The reason? Your booty.

Turns out, your hindquarters just don't tan as well as the rest of you. Instead, your derriere is more likely to simply turn red - probably not the look you were going for.

LiveScience reported on the new research conducted by scientists from the University of Edinburgh who were trying to learn why different skin cancers tend to be found in different parts of the body. Researchers exposed the back and the behinds of 100 volunteers to UVB rays, the type that cause sunburns. The findings? Some parts of your body respond differently to the sun, hence the red hiney.

But regardless, you probably shouldn't be soaking up the rays anyhow, either under the sun or in a tanning booth. The rate of skin cancer is on the rise, including melanoma, the deadliest form. Last year, international cancer experts called tanning beds as deadly as arsenic and mustard gas.

If that's not enough to instead send you to the self-tanning lotion, do it to avoid having a baboon bum.

What's your weirdest or worst sunburn? Tell us about it in the comments or, better yet, send us a photo. We'll publish some of the best pictures.

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