Some ideas for you, Patti...
I am also a grad student (have been for 5 years!). I've found some
things that work pretty well for me...satisfies that "need" to munch
when I study. (I think it's just nerves...).
I keep an air popper in my office and a jar of popcorn--a couple of
shakes of popcorn, and I've got a small bowl to get me through at least
a few journal articles. I also have access to a microwave so that I can
make flavored coffees (fat-free, sugar-free). I have found that these
two things in combination really satisfy that "munching" thing, as well
as my sweet tooth. If you don't have access to a microwave, one of
those electric things that you stick in a coffee mug would work, too.
Of course, if you're studying at home, probably neither of those things
is a problem!
I also keep at least one piece of fruit on my desk...and a knife. I
slice an apple into 8 pieces and nibble on it while I'm reading. A cup
of cold grapes are pretty satisfying, too.
These food/reading things are probably not a good habit to get into, but
it's what gets me through--and these food choices are a lot better than
a bag of candy or package of cookies! Looking forward to seeing what
other people suggest! Good luck!
Cat (Catherine) Skinner