Indeed it states in Deuteronomy (8:3) that, in this case the miracle preformed in the wildnerness, that through it you should "know that man does not live by bread alone, but by the every word that comes from the mouth of Hashem does man live". Additionally the Mishne from Pirkei Avot (Ethics of our Fathers) 3:21 states:
"Rabbi Elazar ben (son of) Azariah said: If there is no Torah [study] there is no proper conduct; if there is no proper conduct there is no Torah [study]. If there is no wisdom there is no fear of G-d; if there is no fear of G-d there is no wisdom. If there is no knowledge there is no understanding; if there is no understanding there is no knowledge. If there is no flour there is no Torah; if there is no Torah there is no flour."
The last aphorism equates a relationship of sustenance related to some issues ripped from today's headlines - that without a job, one's Torah learning will not be sustainable. But in the tefilla frame of mind, one must also remember that we are not monks who frown upon food and the material world - but rather we relish and sing in the delight of Shabbat and holidays as well as in the houses of study and prayer.
So it brings me back to what I think about on a fast day - the historical shadow of the day or my craving to nosh on food.... I think about both.