There is a book called "sugar blues" and is about the intake of Sugar and how it affects low mood. Don´t know the author, probably you can find it in the web.

very keen observation on your part...
you will go far "grasshopper"... lol... ;-)

diet does play a vital role in health... yet the fact is that Sugar may have an entirely different effect on someone else...

perhaps it would help you understand a little better if you read some of the info that's available by clicking on the blue bar at the bottom of the "curezone" header that says "health"... has some very informative reading... especially "eat right for your blood type"... //www.curezone.org/diet/blood_type.asp

this site has an abundance of healthy information...

best wishes...
lol...
;-)