US chicken companies pioneered restricting sleep to keep birds eating around the clock.
A new study (Li et al., 2026) recommends giving chickens just 2 hours of darkness nightly to maximize the time they spend eating. The study and photo are Chinese.
We know chickens have far better hapiness with 7–8 hours of darkness to sleep.
But they eat more when they are sleep restricted.
Even for meat chickens not in cages, they’re bred to be so big and grow so fast they can hardly walk and many just die of heart attacks as they get too big.