Understanding Seasonal Affective Disorder and Seasonal Low Mood

In short

Seasonal affective disorder (SAD) is a pattern of low mood that follows the time of year, most often beginning in autumn as daylight shortens and easing in spring. Seasonal low mood describes the same shape in a milder form.

What this is

Most people expect low mood to announce itself. Seasonal low mood rarely does. It usually arrives as a change in energy and appetite before it arrives as sadness — waking heavier, wanting more sleep than usual, reaching for carbohydrates, letting plans quietly fall away. By the time the flatness is obvious, several weeks of it have often already passed.

The clinical picture, described by services such as the NHS and the National Institute of Mental Health, is a depressive pattern that recurs at the same time of year — typically starting in autumn or winter and lifting in spring — rather than a separate illness. Recognising the pattern early matters, because the things that help most (light, rhythm, movement, contact with other people) are easiest to put in place before the withdrawal has set in.

What this can look like

Ways to reflect on this

Related reading

Tools that can help

Available inside Echo Journey

Frequently asked questions

What is seasonal affective disorder?

It is a pattern of depression that follows the time of year — most often beginning in autumn as daylight shortens and easing in spring. It is described as a seasonal pattern of depression rather than a separate condition.

What are the early signs of seasonal low mood?

Changes in sleep and appetite usually come first: sleeping longer, waking unrefreshed, craving carbohydrates, and gradually withdrawing from plans. Low mood and loss of interest often become obvious only after those.

When does SAD usually start?

Most people who experience a seasonal pattern notice it from early autumn onwards, often building through October and November, with improvement in spring.

Is seasonal low mood the same as depression?

It is the same family of experience with a seasonal timing. Some people have a mild seasonal dip; others meet the full picture of a depressive episode that recurs each year.

Does light therapy help?

Light exposure — daylight where possible, and light boxes for some people — is commonly used and is worth discussing with your GP, alongside routine, movement and contact with other people.

When should I speak to someone about it?

If low mood persists, worsens, or makes daily functioning difficult, speak to your GP or a mental health professional. If you have thoughts of harming yourself, contact your local emergency service now.

If autumn is where this starts for you

Brighten Your Seasons is Hendrina's guided journal for exactly this — written for the weeks before it takes hold, not after. You can start it inside Echo Journey.