Fructose is actually poison (not in the sense of "you die now", but in the long term alcohol sense) with almost no energy benefit. The high fructose corn syrup and sucrose (50% fructose, 50% glucose) used in most candy are remarkably inefficient sources of energy. The fructose provides practically zero and although the glucose in sucrose is good, there are better sources for it.

For source, watch "Sugar: The Bitter Truth" (http://www.youtube.com/watch?v=dBnniua6-oM) and/or look up the research it references.