Social media can have a negative effect on your life because people are mean. You could put up a witty post on FB, or a dashingly attractive picture on Instagram, and then WHAM! Someone posts something that is passive aggressive, or just downright mean. Now, go through this more than a “few” times and it can start to take an emotional and mental toll on a person.
The second way that social media can have a negative effect on your life is through how much you use it. I think it’s like a drug in that sense. Some people just NEED to be on it. They cannot survive or have a mental breakdown if they are not connected to the inter-web world. It’s sad. But true … for some people.