Akiko has been keeping a sleep diary for six months. At first she barely managed five hours a night — work emails, a noisy flatmate, a phone that never left her hand. Slowly, things have changed. She's moved her phone to the kitchen, bought blackout curtains and started a strict 11pm bedtime, even on Fridays. "I've never felt sharper at work," she says. "And I haven't caught a single cold in three months." She still struggles with weekends away from home, but she's stopped panicking about the odd bad night.
