My job is a mixture of things. Sometimes I am working in radio or TV, sometimes I am writing for a newspaper with a deadline just a few hours away and sometimes I am writing a book with a deadline two years away. And today I might be writing about cosmology and trying to convey some complicated physics, whereas tomorrow I might be writing about mumbo jumbo pseudoscience and talking to lawyers to make sure I am not going to get sued for libel.
Although my background is in physics, this included a huge amount of mathematics, and that part of my training was very important. To be a writer or journalist you need to think logically and creatively, and mathematics involves both these skills. If you are interested in being a journalist, then I would certainly recommend taking a degree in maths or science rather than a degree in media studies. Learning to write is relatively easy, once you have a foundation and confidence in the subject you want to write about.