Seasonal Depression: Common Signs To Look Out For

What is seasonal depression?

Seasonal depression causes feelings of sadness and hopelessness that overlap with daylight hours changing. When seasonal depressive symptoms affect your day-to-day activities, you could be experiencing the seasonal affective disorder. 

Seasonal affective disorder (SAD) is a type of major depressive disorder that typically occurs when the daylight hours start to shorten. It usually occurs in the fall or winter and disappears during the spring and summer months. 

However, there is evidence that a small proportion of the population can experience it in the summertime and feel better during the winter months. 

This disorder significantly affects your life more than the winter blues or summer sadness. It can affect your sleep, energy, appetite, and emotional states. 

Causes and risk factors

Why SAD occurs is not exactly known; however, it is accepted that reduced sunlight exposure is a crucial factor in most cases.

Seasonal depression is common. It is reported that approximately 20% of the population¹ will have mild depression symptoms, and 5% of the population¹ will experience SAD.

Risk factors include:

• Being a female

• Being 18 to 30 years old

• Living in countries further away from the equator

• Presence of other mental health conditions 

• Having a family history of SAD

Signs of seasonal depression

So, what are some common signs to look out for?

Changes of emotion

Depression is the primary feature of seasonal affective disorder. However, people with summer SAD may experience irritability as their main symptom. 

SAD is generally associated with feeling down and hopeless more days than not.

The severity of depression is highly uneven among people with SAD. Despite this being your psychological condition, people around you will most likely be affected, including your friends, family, and colleagues, who would also feel the effects of your low mood. 

If you are worried that you have seasonal depression, ask someone around you if they have noticed any changes to your mood. 

Unable to find pleasure in hobbies

Being unable to feel pleasure in things you used to has been associated with seasonal affective depression and is typical of those feeling depressed. Your hobbies might feel more like a chore than a pleasure. 

For example, being with your pet made you feel happy, but now you struggle to play with it and find it annoying and tiresome.  

Changes in sleep patterns

Sleep is essential to the body for mood regulation and memory formation. 

The average adult should sleep approximately 7–9 hours per night. The quality of sleep and a lack of or excessive sleep can profoundly influence mood, and sleep disruptions are a common issue in depression.

Increased periods of sleeping and/or increased periods of drowsiness during the day

SAD can significantly alter your sleeping pattern. 64–84% of people with seasonal affective disorder² self-report an increased proportion of sleep ranging from 30 minutes to two hours per night. It may also be very difficult to leave the bed in the mornings.

Despite sleeping more, people with SAD do not feel more rested. In fact, increased drowsiness during the daytime is another common symptom.

Excessive sleepiness in SAD is due to melatonin, a chemical that signals our brain when it is nighttime. It is produced by the pineal gland in response to darkness and plays a major role in matching your internal clock with the outside environment. 

As the days begin to shorten in the winter season, your brain increases its melatonin production, resulting in your body feeling tired. Melatonin levels³ also tend to increase in people with SAD.

This partial explanation aligns with the effectiveness of light therapy to treat this disorder. 

Light therapy aims to increase the amount of light our brain receives through lightboxes that emit visible light. It has been found to improve symptoms in 65% of people with SAD⁴.

Changes in behavior

SAD may also result in noticeable behavioral changes. Typically, people with SAD will withdraw from their environment, and you might find yourself withdrawing from your environment in multiple ways. 

You might spend less time outdoors or with people, adding to your feelings of loneliness and isolation. 

Lack of motivation

Lack of motivation is commonly found in people with SAD. This is essentially the feeling of “dragging your feet” when committing to any plan that requires effort. 

Although you want to attend, you feel like you can’t be bothered and will not participate. 

For example, you might message your friend that you want to meet for a coffee but never get around because it seems too hard. It may even be difficult to shower or brush your teeth in severe cases. 

Lack of energy

If you are experiencing SAD, you may feel tired all the time. This would significantly affect multiple aspects of your life, as you might start to default to doing less and less.

You might stop exercising because you're too tired or make mistakes because you can’t concentrate or focus. 

Changes in eating patterns

SAD can trigger unhealthy eating habits, including:

Overeating and cravings

SAD is associated with poorer health choices in terms of food. People with the seasonal affective disorder tend to eat more than they usually would or crave food that is sweet or high in carbohydrates.

They can also experience isolated episodes consistent with those suffering from binge eating disorders. Recent research found that approximately 27% of their participants with SAD⁵ reported episodes of binge eating.

This result was only found among females.

Weight gain

Over-eating and craving high-calorie “comfort foods” can lead to weight gain. Lower activity in winter can also worsen this issue. 

Research has found a link between weight gain and people with SAD⁵. The amount of weight would be highly variable on these factors and the individual. Gaining weight can further add to the stress on the body and mind.

What is required for the diagnosis of SAD?

To be diagnosed with SAD, you need to be diagnosed with major depressive disorder and have experienced symptoms for two or more years with:

• Symptoms presenting at the same time each year

• Symptoms disappear at the same time each year

• Symptoms appearing at the same time each year outweigh symptoms occurring during the other period.

This disorder will likely reoccur in the following year, with 40% of people⁶ having reported repeating symptoms the following year. It is essential to get help and learn how to take preventative measures if you are concerned.

What are the treatment options?

The treatment of SAD ranges significantly. Light therapy is generally the first-line treatment that is relatively non-invasive. 

Typically, this involves a broad-spectrum 10,000 lux lightbox emitting visible light on an individual for 30-90 minutes each morning for at least six weeks.

Other therapies include antidepressants medication, vitamin D replacement, counseling, and cognitive behavior therapy. 

People with SAD can also benefit from lifestyle changes such as exercising regularly, eating healthy food, avoiding alcohol, maintaining a healthy sleep pattern, and partaking in social activities. 

If you are concerned that you are experiencing SAD, contact a healthcare professional to learn more about your condition.

The lowdown

Seasonal depression is a common disorder that can affect anyone. Milder symptoms are experienced by one in five people. If these symptoms cause major disruptions to your life, it may be classified as a seasonal affective disorder.

Seasonal depression can significantly impact your life, and if you are worried that you have SAD, it is advised to seek medical intervention.