Although Planet's native life is based, like Earth's,

Although Planet's native life is based, like Earth's, on right-handed
DNA, and codes for all the same amino acids, the inevitable chemical
and structural differences from a billion years of evolution in an
alien environment render the native plant life highly poisonous
to humans. Juicy, ripe grenade fruits may look appealing, but a
mouthful of organonitrates will certainly change your mind in a hurry.

-- Lady Deirdre Skye,
"A Comparative Biology of Planet"

Related:

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