I'm not sure if it would de-index your site BUT it will definately not help. You need a balanced link profile from good authority sites with both followed and no follow links (obviously more followed). If you just have a link profile with just followed links and they are all from directory sites (which tend to have low authority - not all but most) you will risk google penalising you.
I would recommend creating a balance strategy to link buidling. Posting in Blogs with a high readership and good reputation, joining a popular and well used forum and actively get involved, a hand full of directories with non spammy links, social sites, news or information sites (email them and ask for a link).... These are just a few ideas... Also you want to make sure your links are balanced and use a variety of different anchor text and not overly optimised keyword text.
Google's algorithm is updated 100's of times a year so you never know when they will start penalising a certain type of link or text or tags etc...
EDIT: Found something that shows a great idea for a strategy and I strongly success you read it!
http://pointblankseo.com/link-building-strategies