The Link Between Depression and Insomnia

Medically reviewed by Dr. Mark Hrymoc, M.D.

There is a clear link between depression and insomnia. The Sleep Foundation reports that 80% of people with depression experience insomnia. At the same time, 40% of those with insomnia report having depressive symptoms. The connection between sleep and mental health is undeniable. For example, sleep disturbances are a symptom of depression, or sleep deprivation can trigger the onset of depression. 

Other reports on mental health and sleep claim that people with depression who improve their sleep quality also improve their mental health. Information like this makes you question which comes first, depression or insomnia. The answer varies depending on individual risk factors. To learn more about the link between your depression and insomnia, learn as much as possible about each separately.

What is Depression?

The American Psychiatric Association defines depression as a mood disorder that makes people have persistent sad feelings. Sadness sticks around for two weeks or longer and can interfere with daily functioning. Also, it is much more than the sadness you feel when grieving, which tends to ease over time.

How is Depression Diagnosed?

Mental health professionals use the Diagnostic and Statistical Manual, fifth edition (DSM-5), to determine if someone meets the criteria for a diagnosis of depression. Five of the following criteria must be present:

  • Depressed mood for most of the time
  • Loss of interest in activities you once enjoyed
  • Change in appetite and weight
  • Slowing of thoughts, speech, and physical movements
  • Lack of energy and feeling tired for no apparent reason
  • Feeling hopeless, worthless, or guilt
  • Trouble concentrating and making decisions
  • Suicidal thoughts or attempts

These are not the only depression symptoms. Sleep disturbances are a common occurrence among those with depression. Other symptoms include anxiety, restlessness, agitation, crying, isolation from others, agitation, physical aches, and being easily angered. 

What Causes Depression?

Many risk factors must be present for someone developing a depressive disorder. However, not everyone with depression will have the same risk factors. Risk factors are the things that make it more likely that you will develop a mental health disorder, not a guarantee. 

Risk factors for depression include the following:

Chemicals in Your Brain

Neurotransmitters are brain chemicals that send signals to the body, telling you how to feel. The neurotransmitters associated the most with depression include serotonin, dopamine, and norepinephrine. Until recently, chemical imbalances have been touted as the leading cause of depression. Today, researchers find that the cause is much more complex and must include other risk factors.


Anytime genetics is mentioned with depression, you may have inherited a gene associated with depression from your family. Having the gene does not guarantee you will have depression, though. The gene, combined with other risk factors, increases your odds.

Physical Disorders

Some medical conditions affect your mood. Hypothyroidism, chronic pain, heart disease, cancer, lupus, diabetes, HIV, and multiple sclerosis are some good examples. 

Nutritional Deficiencies

If your body does not get the nutrients it needs to function correctly, your mood will be lower. Research shows that the nutrient deficiencies most linked to people with depression include omega-3 fatty acids, vitamin B, magnesium, and zinc.


Hormonal fluctuations can affect mood changes, like when a woman is pregnant. Prenatal, perinatal, and postpartum depression are due to hormonal shifts. Menstruation can also cause mood swings due to hormone changes.

More Risk Factors

Additional factors present with depression include seasonal changes, like winter, when there are fewer hours of sunlight. Also, past traumatic experiences include abuse, surviving a natural disaster, war combat, substance misuse, stress, medications, and sleep deprivation.

What is Insomnia?

Insomnia is when you have trouble falling or staying asleep. If you’ve ever done everything right to prepare for a good night’s sleep but still couldn’t get it, you may have insomnia. It is a sleep-wake disorder that can be either short-term or chronic.

Short-term insomnia lasts between one and three months. Chronic insomnia lasts longer than three months and is recurrent. With either type, you experience symptoms at least three nights per week.

How is Insomnia Diagnosed?

Before a mental health professional can diagnose you, they must see a record of your sleep habits. Keeping a sleep diary will likely be required. Your diary can help identify lifestyle changes that may help you sleep better. Other essential information for a diagnosis includes your physical health and medical history, blood tests, and possibly a sleep study.

The diagnostic symptoms include the following:

  • It takes you longer than 20 to 30 minutes to fall asleep
  • Waking up throughout the night and having trouble falling back asleep
  • Waking up at least 30 minutes early without getting at least 6.5 hours of sleep

What Causes Insomnia?

Like depression, the causes of insomnia may differ for everyone and are dependent on personal risk factors, such as genetics and brain activity. Also:


Your daily habits, good or bad, can influence your sleep. Alcohol and drugs interfere with quality sleep. Even if the substances lead to unconsciousness, you are not getting quality sleep. Smoking, sleeping with the television on, scrolling social media right before bed, and drinking too much caffeine late in the day will influence sleep. Further, not having good sleep hygiene or keeping a sleep routine will hinder sleep.

Making small changes to your lifestyle can lead to improvements in how your sleep.


If you have anxiety or stress, neurological issues, other sleep disorders, mental health disorders, or physical conditions, they may be causing your sleep disturbances.

The Link

When you sleep, your brain restores your body and mind, so you feel refreshed and energized the next day. Without restorative sleep, it is difficult to overcome depressive thoughts. The more depressive thoughts you have, the more challenging it is to get quality sleep. The link is a vicious cycle that affects each person differently.

The good news is that a psychiatrist and other mental health professionals, like those at the Mental Health Center, can successfully treat depression and insomnia using a combination of medications, therapies, and alternative treatments. In a short time, you can notice major improvements.