People learnt a long time ago that getting into full blown discussions at work and in the office about sex, religion and politics are a very touchy aspect. They are bound to always end up going in the wrong direction (by this I mean a major disagreement). The fact of this is because you can either offend a colleague or get into a full blown out of proportion argument.
Below are a few facts why talking about these types of subjects, can be a very hazardous approach.
First and foremost if you do not want to get into an argument within a group discussion, do not just say silent. The saying that silence is golden is not necessarily true for this occasion, as some people may feel as if you are agreeing to aspects if you do not open up and speak. The best thing to do in all honesty is to walk out of the room, but if you are stuck then you should make your feelings clear that you do not want to be part of the conflict.
When people speak about politics, especially if they of an extremist nature, they tend to get all worked up. So avoiding any discussions of politics in the work place, would be the best bet, as team spirit has the potential to be broken by a wave of insults. The only thing that can end up happening once team spirits are broken is work not being completed to full satisfaction.
Even if you agree with each other in your discussions and are on the same wave length, this can still spell a recipe for disaster. You may well be overheard or understood by a different variety of other characters. Which could ultimately end your career promptly.
Political and religion chit chatter are not really classed as discussions, because people do not want to talk they just want to constantly put there views across. A lot of these so called discussions always end badly. It will result in a lot of hard feelings even after the conversation has ended.
My final point would be, you are at work to work and that is it. Unless you are being paid to discuss these topics, which is highly unlikely, I would steer well clear, because besides from getting on the wrong side of your colleagues you may very well upset your boss, who may then decide to leave you unemployed.