The Collaborative International Dictionary of English v.0.48:

malnourished \malnourished\ adj.
   Not getting adequate food; suffering from malnutrition;
   underfed. [Narrower terms: starved, starving; unfed;
   foodless]
   [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

Unfed \Unfed\
   See fed.

WordNet (r) 3.0 (2006):

unfed
    adj 1: not fed
    2: not given support; "a grudge that remained unfed"

Moby Thesaurus II by Grady Ward, 1.0:

27 Moby Thesaurus words for "unfed":
   Lenten, bare-handed, beggarly, empty-handed, famished, fasting,
   half-starved, ill off, ill-equipped, ill-furnished, ill-provided,
   impoverished, on short commons, pauperized, poor, quadragesimal,
   shorthanded, starved, starveling, starving, underfed, undermanned,
   undernourished, uneating, unprovided, unreplenished, unsupplied