Seasonal affective disorder (SAD) – how to cope

Seasonal affective disorder, or SAD (also known as seasonal depression) is a mental health condition and a form of depression that happens in a pattern during a particular season each year.

It can affect people in both winter and summer, although it’s rarer to get it in summer. More commonly the symptoms begin in fall or winter and ease up by spring.

Many people may experience a form of “winter blues”, where they start to feel down as the weather gets colder and the days get shorter. While the “winter blues” can be mild, in people with SAD the symptoms can have a big impact on mood and behavior.

The good news is there are effective self-care strategies and treatments available, so you don’t have to feel low all winter or summer with these feelings.

Seasonal affective disorder symptoms

With seasonal affective disorder, you may have some of the common symptoms of depression, but the difference is that these symptoms emerge when the seasons change and tend to last for 4-5 months of the year.

Symptoms can also vary depending on whether you get SAD in the winter or summer.

Common symptoms include:

• feeling low, sad, or ‘empty’ most of the time, every day for 2 or more weeks
• feeling guilty, worthless, or hopeless
• feeling irritable
• loss of interest in things you usually enjoy
• having less energy or feeling fatigued
• finding it hard to concentrate
• withdrawing from friends and family – which may affect your relationships and work
• losing your sex drive (libido)
• having thoughts about hurting yourself, if you have severe depression (find out how to get help if you’re having suicidal thoughts).

Winter pattern SAD symptoms

In addition to experiencing some of the above symptoms, if you have winter pattern SAD, you may also:

• have an increased appetite and craving for “comfort foods” high in carbohydrates, like pizza, bread, or cake
• gain weight from overeating
• have hypersomnia – where you sleep for longer than normal and might find it hard to get out of bed in the morning
• be socially isolating yourself and feel like you’re hibernating.

With the winter blues, although you’ll get some low mood symptoms, which come on with the change in season, they’re milder than SAD. You may get some of the symptoms above, but your day-to-day life won’t be as affected.

For example, research has found people with SAD say they sleep an average of 2.5 hours more in winter than summer, whereas people with winter blues say they sleep 1.7 hours more.

Summer pattern SAD symptoms

With summer SAD, you may get symptoms of depression such as:

• loss of appetite, which can lead to weight loss
• difficulty sleeping (insomnia)
• feeling restless and agitated
• anxiety
• violent or aggressive behavior.

Watch a video of founding SAD researcher Dr Norman Rosenthal talking about his own experiences of SAD.

What causes it?

While we don’t know exactly what causes seasonal affective disorder (SAD), there are several theories. The most well-known is that it’s caused by reduced exposure to sunlight.

This is thought to affect your body in the following ways:

• your brain works differently – the part of your brain that helps control your mood, appetite, and sleep (the hypothalamus) stops working properly
• your sleep patterns change – these brain changes may affect your ‘sleep’ hormone, melatonin, leading you to sleep more than normal
• you produce less ‘feel-good’ hormone, serotonin, which may cause low mood
• your internal 24-hour body clock may be disrupted (circadian rhythm), so your routine is out of sync.

This theory explains why winter SAD occurs, but what about seasonal depression in summer? Some experts believe that summer SAD is caused by longer days and warmer weather disrupting your sleep quality, leading to depression, but more research is needed.

Who gets seasonal affective disorder?

There are also some other things that may mean you’re more likely to be affected by seasonal affective disorder (SAD):

• being female – women and people assigned female at birth are more likely to develop seasonal depression than men
• your age – SAD is most common in younger adults between the age of 18 and 30
• your family history – you may be more likely to develop SAD if a family member also has it, or another mental health condition such as depression
• other conditions – people with SAD are also more likely to have other mental health conditions, such as attention deficit hyperactivity disorder (ADHD) or eating, panic, or anxiety disorders, depression, or bipolar disorder.

When to see a doctor

Speak to your doctor if you think you might have seasonal affective disorder and you’re struggling to cope with the symptoms.

Your doctor can rule out other health conditions that may be causing your symptoms, such as underactive thyroid (hypothyroidism), low blood sugar (hypoglycemia), infectious mononucleosis (glandular fever), and other viral infections.

If you’re feeling severely depressed, or have suicidal thoughts, you should go to your nearest emergency department immediately.

How to diagnose SAD

Your doctor may carry out a psychological assessment on you and ask you some questions, including about:

• your mood
• your lifestyle
• your sleeping pattern
• your eating habits
• the seasonal changes to your mood or thoughts
• your family history of mental health conditions, such as a family history of depression.

Your doctor may also carry out a physical exam and tests to check for other health conditions.

To diagnose SAD, your doctor will look to see if your depression has a seasonal pattern, starting at a similar time of year for at least 2 years in a row.

Treatments to combat seasonal depression

If you’re diagnosed with SAD, there are 3 main recommended treatments:

• light therapy and/or dawn simulation
• antidepressants
• talking therapy (psychotherapy)

You and your doctor will decide on the right treatment for you, based on how severe your symptoms are and how you’re coping with them.

You may need a combination of treatments, and it can take time to find what works for you.

Lifestyle changes, such as self-care tips, can also help.

Light therapy for winter depression

Light therapy, or phototherapy is a treatment for SAD in the winter that involves sitting in front of a specialized lamp called a light box for 30-60 minutes each morning.

The idea is that the lamp mimics natural light that you're missing in the winter months. This is thought to encourage your brain to produce the good mood hormone serotonin and less of the sleepy hormone melatonin.

For most people, light therapy is safe, however, if you’re sensitive to light because you have an eye condition, eye damage, or are taking certain medication, such as antibiotics, it might not be suitable for you.

Speak to your doctor about whether or not light therapy would be suitable for you.

Watch this video about how light therapy works.

Antidepressants

Antidepressants are often recommended alongside light therapy:

• they’re thought to be most effective if taken before the start of winter, as they can take around 4 to 6 weeks to have an effect
• they should be slowly reduced at least 2 weeks after the end of the winter season
• they can include selective serotonin reuptake inhibitors (SSRIs), such as sertraline and fluoxetine
• if you don’t respond to SSRIs or can’t take them, bupropion may also be used, but it’s only available for this condition in some countries. This increases a brain chemical called dopamine, which is involved in calming and pleasure sensations.

Psychotherapy

Psychological treatments are also often recommended, either alone or in combination with other treatments:

• cognitive behavioral therapy (CBT) is based on the idea that how we think and behave affects the way we feel. It can teach you to challenge dysfunctional thoughts about winter, and change behaviors such as socially isolating (hibernating). CBT adapted for SAD has been shown in trials to be helpful, with remission expected in about 50% of cases
• counseling is another type of talking therapy that’s sometimes used, as is psychodynamic therapy – which involves looking into how your past may affect how you feel today.

Self-care tips to manage SAD

While you may also need treatment from your doctor, there are some simple lifestyle tips you can try to help you cope with SAD:

For SAD in the winter, tips include:

• going outside for a walk every day – bright midday sun gives off the most light, but you’ll still benefit from outdoor light on cloudy days
• sticking to a routine – get up and go to bed at the same time every day, so you don’t sleep too much, and sleep only when you feel sleepy
• having bright light indoors – try sitting by a window while at work or home during the day, and turning on lamps, as well as overhead lighting in the evening
• avoiding too much light exposure in the 2 hours before bed – including blue light from your phone, computer, TV, and other electronic devices
• doing regular aerobic exercise – such as brisk walking, running, or gym workouts to boost your mood
• keeping up social connections – don’t stop making plans to meet up with friends and family
• try journaling – take note of your symptoms and when they happen to better understand patterns in how you’re feeling.

For SAD in summer, try:

• limiting your time in natural daylight – get no more than 13 hours a day, and keep out of the sun when it’s at its hottest
• staying cool, especially at night – loose clothing, fans, or air conditioning can be helpful
• keeping hydrated – by drinking plenty of water
• planning social activities indoors – meet friends in a café or at the movies to stop yourself becoming isolated.

Getting support

Global help: Find support and information from a list of resources on the International Society for Affective Disorders website

In the US: contact the Suicide & Crisis Lifeline by calling 988 toll-free, or using the website’s Lifeline Chat. Or contact the Crisis Text Line by texting HOME to 741741.

In the UK: contact Samaritans for free from any phone by calling 116 123. Or check mental-health charity Mind’s list of crisis helplines.