Most Delicious Poison

August 28, 2023
This amusing debut from Whiteman, an evolutionary biology professor at UC Berkeley, explores the “ways that toxins from nature arose, have been used by us humans and other animals, and have consequently changed the world.” Natural toxins including capsaicin (the chemical that “produces the heat we feel when we eat chilies”) and morphine evolved to protect plants from herbivores, Whiteman explains, noting that coffee plants developed caffeine as a natural insecticide capable of killing predatory beetles, butterflies, and mosquitoes (humans’ larger bodies are able to metabolize significantly larger doses, tempering the poisonous effects). Digging into the biochemistry of how toxins work, Whiteman observes that ethanol mimics the GABA neurotransmitter that the “brains of all animals use to dampen the activity of the nervous system,” binding to GABA receptors and causing sleepiness. There’s plenty of fascinating tidbits (mild toxins in saffron might be as effective at treating depression as Prozac), but Whiteman’s personal stories can be hit-or-miss, with touching reflections on his father’s battle with alcoholism appearing alongside superfluous anecdotes about his dog narrowly surviving after eating caffeine pills. Still, this is worth a look.