Many people recommend cultured vegetables - sauerkraut, kimchi...
pros: you can make them at home cheaply and can buy them in some places; it's food!
cons: if you make them at home, it'll take some time & practice (sometimes people have problems with mold)

Other ideas: there are lots of good food products you can make or sometimes buy like the above...check out the Weston A. Price Foundation's website (there are drinks, like kvass, kombucha)...these are said to have detoxifying properties as well.