Disabling the Sites Cache

All,

I'm new to Sites and website development, but doing okay. I have a client facing public portal up and running. The issue is that when i change data in the record in SFDC that the page is built from, the data takes a while to make it through a user's cache. So, it's not truly a dynamic page like we need it to be (the page needs up to the moment data).

Is there a way i can disable the caching of the page in my viewer's browsers? it's also a major issue with testing!

Thanks!