Study researcher Renee Biss, a graduate student at the University of Toronto, said one of the reasons morning people may be happier is because they tend not to suffer from social jet lag.

CNN: STORY HIGHLIGHTS

At the moment, Ptacek sees his research having the most direct applications for those who suffer from night eating disorder, difficulty with jet lag, and the problems associated with working graveyard shifts.

FORBES: Holiday Overindulgence Got You Down? Blame Your 'Food Clock'

Travel like this can be exhausting, and I suffer from all the typical air warrior ills: constant tinnitus, frequent sinusitis, dry eyes, jet lag and a bad back.

FORBES: Madison, San Francisco, Beijing