I don't think replacing any addiction with another type of addiction is healthy. Some people find that anything can become addictive once you get that obsessive like thinking. I remember the first time I got sober I became a health FREAK! hah would you believe I logged calories, worked out every day, and really replaced drugs with exercise.
Some might say that's healthy, but nothing is healthy when it's not done in moderation, ya know? Instead, invest your time in healthy, sober activities, maybe get into reading books by a certain author, watch movies you've never seen before, exercise some to get endorphins flowing, etc.. Just watch out for substituting an addiction, it's easy to do so keep any non-moderated behavior in check!
Stay safe,
Rach