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Three billion people, around 40% of the world’s population, use online social media – and we’re spending an average of two hours every day sharing, liking, tweeting and updating on these platforms, according to some reports. That breaks down to around half a million tweets and Snapchat photos shared every minute.

With social media playing such a big part in our lives, could we be sacrificing our mental health and well-being as well as our time? What does the evidence actually suggest?

Since social media is relatively new to us, conclusive findings are limited. The research that does exist mainly relies on self-reporting, which can often be flawed, and the majority of studies focus on Facebook. That said, this is a fast-growing area of research, and clues are beginning to emerge. BBC Future reviewed the findings of some of the science so far:

STRESS

People use social media to vent about everything from customer service to politics, but the downside to this is that our feeds often resemble an endless stream of stress. In 2015, researchers at the Pew Research Center based in Washington DC sought to find out if social media induces more stress than it relieves.

In the survey of 1,800 people, women reported being more stressed than men. Twitter was found to be a “significant contributor” because it increased their awareness of other people’s stress.

But Twitter also acted as a coping mechanism – and the more women used it, the less stressed they were. The same effect wasn’t found for men, whom the researchers said had a more distant relationship with social media. Overall, the researchers concluded that social media use was linked to “modestly lower levels” of stress.