Hi,
be expected to vary depending on his recent diet, or perhaps whether he has been ill recently. I have heard occasional references to the idea of diagnosing people of various illnesses based on the presence of minute amounts of chemicals in breath (a neat idea, BTW).
There is some serious research about this: - https://www.youtube.com/watch?v=1i-Rx-Nsf3E - http://www.nature.com/bjc/journal/v103/n4/full/6605810a.html - http://pubget.com/paper/18594325/analysis-of-volatile-organic-compounds-in-t... - http://www.jthoracdis.com/article/view/1560/html A little older research: - http://www.foxnews.com/story/2007/02/28/breath-odor-can-be-key-to-detecting-... - http://news.bbc.co.uk/2/hi/health/3682722.stm - http://gut.bmj.com/content/early/2011/01/17/gut.2010.218305.short?q=w_gut_ah... P. S: If anyone has any recent information about this (especially clinical tests), please let me know. It is an area which is of a great interest to me. Regards, Matej