Medical Review by Jennie Stanford, MD, FAAFP
Summary:
- Being able to tell the difference between depression and seasonal affective disorder (SAD) can make it easier for you to find appropriate treatment.
- Depression and SAD have similar symptoms, but SAD follows a seasonal pattern—typically emerging in fall or winter and easing in spring.
- While depression causes persistent sadness, fatigue, and loss of interest in activities, SAD symptoms vary by season—winter-pattern SAD often includes oversleeping and weight gain, while summer-pattern SAD can lead to insomnia and anxiety.
- A medical professional can use questionnaires and other methods to help you diagnose either of these conditions. SAD diagnosis requires experiencing seasonal depressive episodes for at least two years.
- Medical guidance is essential for personalized treatment plans. With expert support, individuals can find effective strategies to manage symptoms and improve overall well-being.
It is easy to mistake the symptoms of depression with those of seasonal affective disorder (SAD)—they share many similarities and can overlap in a variety of ways. However, it is important to understand the key differences between these two conditions so that you can find effective help for either one if you need it.
Understanding whether you are dealing with symptoms of depression or SAD can guide the conversations you have with your healthcare practitioner. From there, you can work with them to create a plan that gets you back to feeling your best. Below, our team at Lemonaid Health explores how these two conditions differ, how they’re diagnosed, and when you should reach out for help.
Key differences between depression & seasonal affective disorder
While depression and SAD share many similarities, key differences set them apart. Both conditions can cause a persistent low mood and changes in daily habits. However, SAD follows a seasonal pattern–emerging in fall or winter and easing in spring.
Here are some basic facts about each condition so that you can understand the differences between them more clearly.
Depression
Depression is a mood disorder that causes a persistent feeling of sadness and a loss of interest in things you once enjoyed. It can affect how you think and feel, and how you approach your day-to-day activities such as sleeping, eating, and working.
While everyone experiences moments of feeling sad or low, these feelings generally pass with time. Depression is different—it impacts the mind and body in ways that make it difficult to function normally.
Symptoms of depression can include:
- Feelings of sadness or emptiness
- Losing interest in activities you once enjoyed
- Changes in appetite
- Oversleeping or not sleeping enough
- Feelings of fatigue
- Feelings of hopeless, irritability, anxiousness, or guilt
- Aches, pains, headaches, cramps, or digestive problems
- Thoughts of death or suicide
Seasonal affective disorder
Seasonal affective disorder (or SAD) is a specific type of depression characterized by a recurring seasonal pattern. There are two main patterns for SAD: winter-pattern SAD starts in late fall or early winter and goes away in spring or summer, while summer-pattern SAD causes symptoms in the spring and summer months, although this type is less common.
For winter-pattern SAD, symptoms can include:
- Oversleeping (or hypersomnia)
- Overeating, leading to weight gain
- Social withdrawal
For summer-pattern SAD, symptoms can include:
- Trouble sleeping
- Poor appetite, leading to weight loss
- Restlessness and agitation
- Anxiety
- Aggressive behavior
Learn more: The most common symptoms of seasonal affective disorder & when to seek professional help
Underlying causes & risk factors of both conditions
Depression is a complex condition that can affect anyone, regardless of background or circumstances. Risk factors such as a history of anxiety and low self-esteem can contribute to depression, along with difficult life events like trauma, loss of a loved one, and substance use.
Research suggests that those experiencing winter-pattern SAD tend to have lower levels of serotonin, a neurotransmitter that helps regulate mood. Shorter daylight hours may be the culprit, as sunlight is thought to play a part in maintaining your body’s serotonin levels. Your skin contains a system that seems to be capable of generating serotonin, and which may be activated when you are exposed to sunlight.
SAD also occurs more often in women than in men and may be more common in people who have relatives with other mental illnesses and mood disorders. When you consult a healthcare provider, they will be able to identify the specific risk factors you face for both of these conditions.
How diagnosis & testing differ for depression & SAD
Diagnosing either depression or SAD (or sometimes both) involves a combination of assessments, discussions, and evaluations to better understand your symptoms and their impact. Here’s how each process works.
Testing for depression
When your daily activities have become impacted by a “low” mood or lack of energy, speaking to a healthcare professional about your symptoms can provide clarity—and more importantly—a treatment plan.
The first way that many healthcare practitioners diagnose depression is by using the Patient Health Questionnaire (PHQ-2), which measures for depressive symptoms. If positive, the more in-depth Patient Health Questionnaire (PHQ-9) is then typically used.
The PHQ-2 features two questions about mood, each scored 0 to 3. A total result of 3 or higher indicates a positive result. If your score is positive for the presence of depression, your healthcare provider will move on to the PHQ-9, which features questions about energy levels, eating habits, concentration, and more. The score for each question ranges from 0 to 3.
Results from the PHQ-9 are used to determine the severity of depression in a patient, instead of whether or not depression is present. The degrees of depression that the PHQ-9 determines are:
- Minimal depression: 1 to 4 points
- Mild depression: 5 to 9 points
- Moderate depression: 10 to 14 points
- Moderately severe depression: 15 to 19 points
- Severe depression: 20 to 27 points
Your doctor or healthcare professional will also most likely conduct a comprehensive interview, including questions about your mood, sleep patterns, energy levels, and changes in appetite or concentration.
Learn more: Depression: what it is, symptoms, causes, & treatments
Testing for SAD
If you’re experiencing symptoms of SAD, speak to your healthcare provider about your symptoms. They may ask you to fill out a questionnaire to see if your symptoms match the indicators for SAD.
SAD can often be tricky to diagnose since not all people with this condition experience symptoms every year. To be diagnosed with SAD, you must meet the following criteria:
- You have symptoms of depression, or more accurately, symptoms of winter- or summer-pattern SAD
- Your depressive episodes occur during a specific seasonal time-frame for at least 2 years
- Your depressive episodes happen more often during a specific season than at other times of the year.
Learn more: Understanding seasonal affective disorder: causes, symptoms, & treatment options
What are your treatment options?
There are a variety of treatment options to manage symptoms and improve your well-being, ranging from therapy and medication to lifestyle changes and specialized treatments. Understanding your options can empower you to take the next steps toward feeling back to your usual self.
Treatments for depression
Depression is one of the most common mental illnesses, with symptoms that can potentially last for years. Long-term treatment is an important way to help shorten depressive episodes and relieve your symptoms. Treatments for depression may include:
- Psychological treatments such as cognitive-behavioral therapy (CBT) and systemic therapy
- Medications, like antidepressants or antipsychotics
- Lifestyle adjustments, including exercise and relaxation techniques
For severe cases where other forms of treatment are not proving to be effective, electroconvulsive therapy (ECT) may also be recommended.
At Lemonaid Health, our US-based healthcare providers can prescribe appropriate FDA-approved antidepressant medications in clinically indicated cases. Learn more about Lemonaid Health’s treatments for depression.
Treatments for SAD
There are a variety of treatments and strategies that can help treat symptoms of SAD. Psychotherapy and antidepressants can treat both winter- and summer-pattern SAD, while light therapy and vitamin D are typically used for winter-pattern SAD. There are currently no treatments specific to summer-pattern SAD.
Our team at Lemonaid Health can also help you find treatment for SAD online. This may include expert one-on-one medical care and medication if clinically indicated for your needs.
Potential for side-effects with treatment
Since every person responds to treatment differently, it may take time to find the plan that best suits you. That’s why it’s important to seek professional guidance and follow your healthcare provider’s recommendations closely.
Antidepressants can cause side effects, whether you’re taking them for depression or SAD. Some of the most common ones include:
- Dry mouth
- Headaches
- Feeling faint
- Restlessness
- Decreased sex drive
These side effects might occur within the first few weeks of taking antidepressants. They usually depend on the type and amount of medication that has been prescribed to you. Learn more about finding the right anti-depression medication for your needs.
Why professional help matters for treating depression or SAD
If you think you have symptoms of any kind of depression—including SAD—you should consult a healthcare practitioner. Medical guidance is an important part of treating depression and SAD because of the potential these conditions have to impact your daily life.
Your healthcare professional can work towards an accurate diagnosis and recommend an appropriate treatment plan for you. Without the proper expertise, your symptoms can go undiagnosed and potentially worsen by negatively affecting your mood and health over time.
Manage your mental health appropriately with Lemonaid Health
Understanding the main differences between depression and Seasonal Affective Disorder is essential for finding the right treatment and support. Working with a healthcare provider can help you understand what symptoms to expect, get a proper diagnosis, and pursue the most effective treatment possible.
Lemonaid Health can connect you with US-based medical experts who can provide advice, answer your questions about either of these conditions, and prescribe medication in clinically indicated cases. Get started today with our team and step closer to feeling like your best self again.
