Jamie Zeitzer

“Indoor light, even in reasonably bright rooms, sits in the 100-to-500-lux range.”

“Step outside on an overcast day and you’re immediately in 5,000-to-10,000 lux.”

“Getting sunlight from a window isn’t really effective, according to Zeitzer, because it only gets you around 1,000 lux, which is a fraction of what’s available outdoors.”