With every new technology comes a wave of panic that it will ruin our lives forever, and smartphones are no exception. A new study adds some much-needed sanity to the debate, making a point that, although obvious, seems to escape most of us: 'Moderation. Is. Key.'

When the telephone first came about in the late 1800s, some people were afraid to touch it because they feared an electric shock, and church-goers used to refer to it as the instrument of the devil.

The television freaked people out on a moral level; TV would hurt "conversation, reading, and the patterns of family living," critics worried, and it would "result in the further vulgarization of American culture."

Finally—and funnily—the arrival of personal computers brought the "moral panic" to an unprecedented level: CNN published a story entitled "Email 'hurts IQ more than pot,'" The Telegraph reported that "Facebook and MySpace generation 'cannot form relationships,'" while the Daily Mail proudly published the piece, "How using Facebook could raise your risk of cancer."

When it comes to smartphones and social media, parents, in particular, tend to panic over their children's moral development and their general well-being, worrying that social media will corrupt the young and ruin their chances of being happy.

While exercising some control and restraint is obviously necessary, we need to apply to new media and new technologies the same principle that we would to dietary fat, alcohol, love, or even exercise: everything in moderation!

This seems to be the main takeaway from a new study that set out to examine whether smartphones really make our teens happy or unhappy.

One hour of screen time daily may be ideal

Jean M. Twenge, the lead author of the study, who's also a psychology professor at San Diego State University, and her colleagues examined the data available from a large survey of more than a million American teenagers.

The survey included questions about how much time the teens spent on their smartphones, tablets, and computers, as well as how often they interacted with their peers face-to-face. The teenagers were also asked about their general levels of happiness and well-being.

Overall, the study found that teenagers who reported more "on-screen" time were, on average, less happy than those who spent more time "in real life."

Engaging in sports or having more face-to-face social interaction correlated with more happiness, while texting, playing video games, and using social media and instant messaging correlated with less happiness.

On the other hand—and this is where the moderation thing comes in—complete screen abstinence did not correlate with happiness either. Actually, the teens who were the happiest reported using digital media a bit under 1 hour every day.

Interestingly, after that 1 hour, unhappiness levels started to rise proportionately with the increasing levels of screen time.

"The key to digital media use and happiness is limited use [...] Aim to spend no more than 2 hours a day on digital media, and try to increase the amount of time you spend seeing friends face-to-face and exercising—two activities reliably linked to greater happiness."

Professor Jean Twenge

Well, that sounds reasonable, doesn't it? Although Professor Twenge's research has been criticized in the past for adding to the scaremongering that surrounds new technology, we think her new study puts forth a pretty sensible idea: technology, like anything else, can be used, but shouldn't be abused.