The data that the NSA collects has little to do with your ISP or IP. Google, facebook, etc... submit all account activity, searches, and messages to the US government on request. That means if you are logged onto google and you make a search, the NSA can ask for the search queries. If you are not logged onto your google account and you use google search, you are safe.
Basically google retains two types of search data:
1) Regional (by IP/country) and they do not submit this to NSA. They do howerver submit it to partner companies that use the data to "sell statistics" to startup firms.
2) Search queries from logged on users. Instant messages. Emails. They submit this to the NSA.
In other words, if the NSA knows that
tt400lebgeeks@gmail.com google account belongs to an american citizen, they may ask google for everything you do while logged onto your google account. This happens regardless of where you are connected from because it is google who gives away your data and not your ISP.
This means that things like Tor only bring a false sense of security against the NSA. It actually is worse since the IP Tor puts you behind is probably snooping on your traffic.
Facebook does the same.
This is all assuming that you are a US citizen living in the US.
So no, dynamic IPs don't protect against the NSA.