Anthropologist Daniel Miller has been studying British teens, and he has a dire message for Facebook: The social network is "dead and buried" to Britain's 16-to-18-year-olds because they're "embarrassed even to be associated with it."

In a recent article for academic clearinghouse The Conversation, Miller shares preliminary findings from a 15-month ethnographic study of social media in eight countries, and explains that Facebook is "so uncool" to teens because their parents and other family members are using it to keep tabs on them.

"You just can’t be young and free if you know your parents can access your every indiscretion," Miller writes. "Young people care about style and status in relation to their peers, and Facebook is simply not cool anymore."

To keep in touch with friends away from mom and dad, Miller found, teens are turning most often to Twitter; photo network Instagram (which is owned by Facebook); to Snapchat, which sends self-destructing photos; and to WhatsApp, a free replacement for cellphone text messaging. That only makes sense.

But it shouldn't worry Facebook or its investors.

The question of whether teens will abandon Facebook has fascinated observers for at least four years (ever since the hysteria over teen Facebook addiction passed). But all that really matters to the service is what happens after teens go off to college and enter "the real world." How will they stay in touch with old friends and connect with new friends as they enter the crucial 18-to-25-year-old demographic in which lifestyle and purchasing habits are formed?

For the most part, this older demographic doesn't turn to tools like Snapchat or Instagram to maintain long-term relationships. Those tools are great for conversing with your immediate social circle, especially when you still live with your parents and have to keep stuff on the down-low. But they're not replacements for a comprehensive social tool you can tailor to all sorts of needs.

Don't take our word for it. Listen to Miller, who writes that even high school teens embarrassed to use Facebook acknowledge its strengths. "Most of the school children in our survey recognised that in many ways, Facebook is technically better than Twitter or Instagram," he writes. "It is more integrated, better for photo albums, organizing parties and more effective for observing people's relationships."

Yes, losing young teens will have some incremental impact on Facebook's revenue at the margins, when, say, movie studio executives are deciding how to advertise a young adult blockbuster. And Facebook should take seriously the problem of drawing boundaries within the system, so information intended for family doesn't leak to friends and coworkers – or vice-versa.

But Facebook co-founder Mark Zuckerberg has been telling people for years that he wants to turn the service into a global utility, akin to the power grid or the water supply – something that feeds everything else you do. Kids don't appreciate utilities. That's just the way it is. But as they get older, they eventually look on them very differently.