Overview
- The term was coined in 2005 by psychologist Cliff Arnall for a Sky Travel campaign using a pseudoscientific formula, and he has since distanced himself from it.
- The 2026 date falls on Monday, January 19, with the phrase trending on X as coverage reiterates there is no evidence for a single most depressing day.
- Samaritans and Mind criticise the concept as harmful and promote alternatives such as the Brew Monday campaign to encourage people to connect.
- Clinicians stress that Seasonal Affective Disorder is real and linked to reduced sunlight, with symptoms including fatigue and hopelessness and about 15% reporting some symptoms in Canadian data.
- Experts advise daylight exposure, daily movement, gradual routine rebuilding, social contact and mindfulness, and they urge seeking help for persistent symptoms, with UK support via Samaritans 116 123, text SHOUT 85258, NHS 111, or 999 in an emergency.