When you receive an email notification saying that a thread that you have subscribed to has had a reply, there is also a link included in the notice that allows you to unsubscribe from the thread. Here is an example copied from one of these notices:

Unsubscription information:

To unsubscribe from this thread, please visit this page:
http://forum.lowcarber.org/member2....ub&threadid=xxx

To unsubscribe from ALL threads, please visit this page:
http://forum.lowcarber.org/member2....&type=allthread


This is the quickest easiest way to unsubscribe.

HTH
Marlaine