This is the best popular science book that I have read. It should be compulsory reading for all school children, as it would help stop the spread of psudoscience and quackery!

A chapter was missing from the first edition of the book due to legal action being taken by rather unpleasant 'nutritionist' against the author. Fortunately, this is now over and the chapter is available for all to read http://http://www.generoom.net/features-story.php?id=58

The Bad Science blog on which the book is based is great too, although I'm guessing most users here know about it already:

 

Edited version at Guardian newspaper site.

 

Original version at Ben's blog.