The best way (performance wise) to exclude a category from front page?

Hi,

I’ve noticed that the query for excluding a category on front page does put a big load on the database (there’s a lot of posts on this wp.

The one i use looks like this:

<?php query_posts($query_string . '&cat=-65'); ?>

Is there any more efficient way of doing this with maybe a smarter query of some sort.

Thank you!