Under 42 minutes of bright daylight linked to higher dementia risk

A study of 87,577 adults wearing light-tracking wrist devices found that average daytime light above 1,000 lux was linked to a 16% lower dementia risk over about eight years. Getting less than 42 minutes of bright daylight daily predicted dementia more strongly than six established risk factors. Night-time light showed no significant link, according to the General Psychiatry paper.