Depression - Symptoms and Causes

Depression is a mood disorder that causes persistent sadness and disinterest in life. It affects millions of people worldwide and can impact anyone, regardless of age, gender, income, or education.

In the U.S., about one in five adults will experience a major depressive episode at some point in their lives. Approximately 21 million adults are affected by depression each year.

What Depression Feels Like

Depression manifests through several key symptoms, which may vary depending on age group.

Emotional changes: Persistent sadness, irritability, or emotional numbness
Physical symptoms: Fatigue, disrupted sleep patterns, and low motivation
Cognitive effects: Difficulty concentrating and negative thought patterns
Behavioral signs: Social withdrawal and avoidance of daily responsibilities

These symptoms can interact and amplify one another, creating a cycle that may be difficult to break.

Depression Symptoms in Children and Teens

Children and teens with depression show many of the same signs as adults, but there are key differences.

Younger children might appear sad, irritable, or clingy. They may complain about physical pain, refuse to go to school, or lose weight unexpectedly.

In teenagers, depression often presents as sadness, irritability, and feelings of worthlessness. They might perform poorly in school, feel misunderstood, or become extremely sensitive.

Some teens may use alcohol or drugs, engage in self-harm, or develop unhealthy eating and sleeping habits. They may also lose interest in hobbies or isolate themselves from friends and family.

Depression Symptoms in Older Adults

Depression isn’t a normal part of aging and deserves proper attention. Many older adults don’t get diagnosed or treated because symptoms may appear differently.

Memory problems or personality shifts
Physical discomfort or pain
Fatigue, reduced appetite, sleep issues, or decreased interest in sex
A tendency to stay home rather than socialize or try new activities
Increased risk of suicidal thoughts, particularly in older men

Diagnosing Depression

Healthcare providers use several methods to diagnose depression:

Physical examinations
Laboratory tests
Mental health evaluations

These assessments help determine the severity of depression and identify the most appropriate treatment options for each person’s situation.

Treatment Options

Depression is highly treatable through various approaches.

Lifestyle Modifications

Making positive changes to sleep habits, incorporating regular exercise, and addressing underlying health conditions can make a significant difference.

Medication

Antidepressants can help balance brain chemicals and reduce symptoms. Since individuals respond differently to each type, finding the right medication may take time and adjustments.

Therapy

Cognitive behavioral therapy (CBT) is particularly effective for depression. It teaches skills to manage negative thoughts and improve coping behaviors, helping break the cycle of depression.

Many people benefit from a combination of these approaches rather than relying on a single treatment method.

When to Contact a Doctor

If you’re experiencing depression symptoms, schedule an appointment with your doctor or a mental health professional as soon as possible.

If you’re unsure about seeking help, talk to someone you trust, like a friend, family member, healthcare provider, or spiritual leader.

When to Get Immediate Help

Call 911 immediately if you or someone you know is experiencing suicidal thoughts or has attempted self-harm.

Causes of Depression

Depression rarely stems from a single cause. Instead, it typically results from a combination of biological, social, and psychological factors:

Factor Type	Examples
Biological	Genetics, family history, chronic health conditions, hormonal changes, brain structure differences
Social	Traumatic events, limited access to resources, lack of support
Psychological	Negative thought patterns, unhealthy coping mechanisms

Brain Chemistry and Structure

Neurotransmitters—chemicals that carry signals in your brain—play a key role in mood regulation. When these chemicals and their pathways malfunction, it can contribute to depression.

Brain imaging studies indicate that individuals with depression may have structural differences in specific brain areas, though researchers are still exploring their significance.

Hormonal Factors

Changes in hormone levels can trigger or worsen depression. These shifts can occur during:

Pregnancy
After childbirth (postpartum period)
Thyroid disorders
Menopause
Certain medical conditions

These shifts influence brain chemistry, making some individuals more vulnerable to depressive symptoms.

Genetic Influence

Depression tends to run in families, suggesting a genetic component. If your parents or siblings have depression, your risk of developing it may be higher.

However, genetics alone do not determine depression—environmental and psychological factors also play a significant role. For example, a genetic predisposition might remain inactive until triggered by hormonal changes or stressful life events.

Risk Factors

Depression can start at any age, though it often begins in the teenage years or early adulthood. Women receive depression diagnoses more frequently than men, possibly because they tend to seek help more often.

Several factors may increase the risk of developing depression:

Personality traits: Low self-esteem, dependency, self-criticism, or pessimism.
Difficult life events: Physical or sexual abuse, losing a loved one, relationship problems, or financial difficulties.
Family history: Having a family history of depression, bipolar disorder, alcoholism, or suicide attempts.
Identity and support: Lack of adequate support for LGBTQ+ and intersex individuals.
Other mental health conditions: anxiety, eating disorders, or PTSD.
Substance use: Substance misuse, including alcohol and recreational drugs.

Physical health issues can contribute to depression risk. Long-term illnesses like cancer, stroke, chronic pain, and heart disease may trigger depression symptoms.

Some prescribed drugs, such as certain high blood pressure medications and sleeping pills, may be linked to depression.

Problems That Come with Depression

Depression is a serious condition that can harm both you and your family. Without proper treatment, it often gets worse and creates problems in many aspects of your life.

People with depression may face several health issues:

Weight gain leading to heart problems and diabetes
Ongoing pain and physical health problems
Substance abuse or dependence

Depression affects relationships and daily life:

Increased anxiety or social withdrawal
Problems at home, work, and school
Social isolation and withdrawal

In severe cases, depression can lead to:

Thoughts of suicide or suicide attempts
Self-harm behaviors like cutting
Earlier death from health problems

Preventing Depression

While no method guarantees prevention of depression, several approaches can reduce risk.

Key Prevention Strategies:

Manage stress effectively. Develop coping skills that build resilience and improve self-image.
Connect with support networks. Include friends and family members, especially during difficult times.
Seek professional help promptly. This can prevent symptoms from becoming more severe.
Commit to ongoing maintenance therapy. This reduces chances of relapse.

These strategies work best when used together as part of a comprehensive approach to mental health care.