In recent years, celebrities have become very well-known for their fashion choices. But by far the biggest source of celebrity news and gossip is the internet and there are thousands of sites dedicated to exactly that purpose.
Although some might view the celebrity fashion phenomenon as an unhealthy obsession, there is actually really nothing wrong with keeping up with the latest in celebrity fashions. While as a teenager you can get away with wearing practically anything, if you are in your 20s, 30s and beyond and still blindly following the latest fashion trend regardless of whether it suits your body shape, you might want to reconsider your fashion habits.
Also, do you really want to be seen wearing something that is instantly recognisable as being a certain brand and that a lot of other people will also be wearing? Of course you can dress like a celebrity if you want to, but you need to remember that celebrity fashions change regularly. There is point going broke trying to afford the "hottest" trend that may only last for a few weeks.
In short, while the celebrity fashion phenomenon won't be over anytime soon, you should approach with caution.