i myself am not that paranoid, but we all now know they have the technology to watch our every move if they so choose.
worried about it? is it possible to limit what they see? i am not so sure, but there are steps we can take to at least try. lets face it, if they really want to watch you they will...but why not make it as hard as possible for those prying eyes (and ears).
steps we have taken in our house include:
-we have switched to using "duckduckgo" for our searches. no it does not seem as thorough as google, but it does good enough for our needs and they claim that they save/store no metadata at all!!
-microsoft and apple of course will give up all of your info in a heartbeat, its linux only in this household. we use ubuntu here with the shopping-lens/amazon integration removed completely. firewall enabled (UFW using the Gufw interface).
-firefox for all web (search engine changed from google to duckduckgo as mentioned above).
-thunderbird for all email.
-also have switched dns servers to the OpenNIC servers both in our router and in ubuntu itself (steps in link below).
of course there is also the Tor browser (in the prtsm-break link below), which is a bit extreme for most of us as well as being just waay tooo slooow. i do have it installed and must admit that it works much better then the times i have tried it in the past few years, but its just not enjoyable surfing at those speeds. therefore it is not used very often.
there are a lot more steps you can take...here are a couple of sites to give you some ideas:
https://prism-break.org/
http://www.opennicproject.org/
http://video.cnbc.com/gallery/?video=3000161097
hope this helps someone.