Recycling g_id values in the database...

Can anyone tell me whether or not the system
generated values for the "g_id" in the database are "recycled"/re-used? (ie. Once used and subsequently deleted, can/will they be re-used?)

Given that the data type for the g_id is int(11)- unsigned and hence has a max value of 2147483647, I am concerned if over time this value would be reached and thus "maxed" out should recycling/re-use not occur. I have noticed that after adding several items, the g_id value seems to keep increasing beyond the highest value in the database, even though lower values are available for use (due to prior deletion of items having lower g_id values).

*I apologize if this has already been addressed in a forum. I've done several searches and for some reason could not find an associated thread that addresses this.*

Thanks...