eating grass...

[Doug Millison]

...has unfortunate long-term effects on the growth and development of
people who find themselves having to do so to survive starvation.  I know
several people who resorted to eating grass, weeds, and tree bark during
the massive famine that plagued China in the early '60s, as a result of the
misguided Great Leap Forward economic development program.  This sort of
starvation can also cause serious long-term psychological damage.

It might be worthwhile looking up the relevant passages about war refugees
and displaced persons and hunger in GR, a novel which treats such
unfortunates with far more sensitivity that the current US leadership does.