Symptoms of Depression: 10 Warning Signs You Can’t Ignore

Depression is a common but serious mood disorder that affects how a person feels, thinks, and handles daily activities. According to the World Health Organization (WHO), a major depressive episode is characterized by a persistently depressed, empty or irritable mood, and often a loss of interest or pleasure in activities, lasting most of the day, nearly every day, for at least two weeks [1]. Unlike ordinary sadness, these symptoms are more severe, long-lasting and can interfere with work, sleep, eating, and social life. In clinical terms, at least five symptoms from a standard list (including depressed mood or loss of interest) must be present to diagnose a major depressive disorder. Recognizing these warning signs early is crucial:

Persistent sadness or low mood: A hallmark of depression is a continual feeling of sadness, emptiness, or irritability that endures for days or weeks. This can look like a person feeling tearful, down, or emotionally “numb” most of the time. World Health Organization (WHO) notes that during a depressive episode, people often feel sad or empty almost every day for at least two weeks [1]. In fact, a recent global review found that about 69% of people diagnosed with depression report a persistent depressed mood. This symptom is typically present most days and is more intense and long-lasting than normal mood fluctuations.
Loss of interest or pleasure (anhedonia): Another core symptom is losing interest in activities or hobbies that used to be enjoyable. People may withdraw from social activities, hobbies, or favorite pastimes and find little satisfaction or pleasure in them. NIMH explains this as “loss of interest or pleasure in hobbies and activities” that used to be enjoyable. Anhedonia is so central that it is one of the key criteria for diagnosing depression. In clinical studies, around 40% of depressed patients report a significant loss of interest [2]. This can manifest as not wanting to go out with friends, a sudden lack of motivation for work or school, or no longer caring about hobbies.
Significant appetite or weight changes: Depression often disrupts normal eating habits. Some people lose their appetite and unintentionally lose weight, while others may eat more and gain weight. These changes are usually marked and not due to dieting or other illness. Health authorities note “changes in appetite or unplanned weight changes” as a symptom. Research shows that around 44% of depressed individuals experience appetite and weight changes [2]. For example, someone may eat far less than usual, feel nauseated by food, or conversely, start eating frequently and gain weight without trying.
Sleep disturbances (insomnia or hypersomnia): Trouble sleeping is very common in depression. This can mean having insomnia (difficulty falling asleep or staying asleep) or the opposite, hypersomnia (sleeping too much). People with depression might wake up very early and be unable to go back to sleep, or they may sleep late into the day and still not feel rested. The NIMH symptom list includes “difficulty sleeping, waking too early… or oversleeping”. Globally, roughly 58% of depressed patients report significant sleep problems. These sleep issues often exacerbate other symptoms (like fatigue) and make coping with daily life harder.
Fatigue or loss of energy: A pervasive sense of tiredness or lack of energy is a classic warning sign. Even small tasks feel exhausting, and the person may struggle to get out of bed. The NIMH notes “fatigue, lack of energy, or feeling slowed down” as a common symptom. This isn’t just normal tiredness, but chronic and often worse in the morning. About 59% of people with depression report severe fatigue or low energy. They may say they feel “drained” or “sluggish,” and their body or mind feels heavy.
Feelings of guilt, worthlessness or hopelessness: Depressed individuals frequently experience excessive self-criticism, inappropriate guilt, or feelings of worthlessness. They may dwell on past failures or blame themselves for things that aren’t their fault. WHO’s overview lists “feelings of excessive guilt or low self-worth” and “hopelessness about the future” among depressive symptoms [1]. Similarly, NIMH highlights “feelings of guilt, worthlessness, or helplessness”. These distorted negative thoughts can fuel a cycle of despair. For example, a person might believe they have failed at everything or that things will never improve. Such feelings are more intense and irrational than normal self-doubt.
Difficulty concentrating or making decisions: Depression often impairs cognitive function. Sufferers may notice trouble focusing, forgetfulness, or indecisiveness. Tasks that require concentration, like reading a book, following a conversation, or making even simple choices, can become unusually challenging. The NIMH fact sheet lists “difficulty concentrating, remembering, or making decisions” as a symptom, and WHO mentions “poor concentration” during a depressive episode [1]. This can look like zoning out in meetings, repeatedly re-reading a sentence but not absorbing it, or feeling mentally “foggy.” Patients frequently describe this as “brain fog,” where thoughts come slowly or seem confusing.
Psychomotor agitation or retardation: Depression can affect physical movement. Psychomotor agitation refers to being restless signaled by pacing, wringing hands, or an inability to sit still. The opposite, psychomotor retardation, involves noticeably slowed movements, speech or thinking. For example, someone might speak in a softer or halting voice, move their body sluggishly, or perform routine tasks much more slowly. Health guidelines note that depression can cause people to move or speak unusually slowly [3]. In research, a substantial subset of patients exhibits these changes. In the NIMH list, fatigue or feeling “slowed down” is mentioned, which often reflects this psychomotor slowing. While not always measured in routine screening, changes in activity level are observed in clinical evaluations of depression.
Recurrent thoughts of death or suicide: Perhaps the most serious warning sign is persistent thoughts about death or suicide. Depressed individuals may talk or think about wanting to die, feel that life isn’t worth living, or even make attempts. Both WHO and NIMH identify this symptom. WHO lists “thoughts about dying or suicide” during a depressive episode [1], and NIMH explicitly notes “thoughts of death or suicide” as a common sign. This goes beyond normal worry and is often a sign of severe depression. If a person frequently fantasizes about death or has a plan for suicide, it is a critical red flag that immediate professional help is needed (see below).
Physical aches, pains or other somatic symptoms: Depression can manifest through unexplained physical complaints. These include chronic headaches, back pain, joint aches, stomach or gastrointestinal distress, or other bodily pains without a clear medical cause. NIMH acknowledges “physical aches or pains, headaches, cramps or digestive problems without a clear physical cause” as symptoms that may not resolve with typical medical treatment. A systematic review found that over one-third of depressed patients report general aches or headaches [2]. For example, someone might frequently complain of headaches or muscle pain, and doctors may find no physical illness explaining them. Such symptoms can obscure the diagnosis, as patients might first seek help from their primary doctor for these pains rather than for emotional distress.

The presence of several of these symptoms, especially when they persist and interfere with daily life, strongly suggests depression. Importantly, not everyone will have all the symptoms, and combinations vary from person to person. However, any cluster of these warning signs, especially over a period of two weeks, warrants attention.

When to Seek Professional Help

If you or someone you know is experiencing multiple depressive symptoms, it’s important to consider professional evaluation. Health experts advise contacting a doctor or mental health professional if these symptoms occur most of the day, nearly every day, for more than two weeks [1] [3]. This timeframe helps distinguish a clinical depressive episode from a shorter-lived “blues.” For example, a person who can’t get out of bed, loses interest in life, and exhibits several symptoms for over two weeks should seek help. The WHO also emphasizes that if you have symptoms of depression, you should seek care, regardless of severity [1].

It’s especially critical to act if thoughts of self-harm or suicide arise. Anyone experiencing suicidal ideation, thinking about suicide, feeling that life isn’t worth living, or making a suicide plan, should reach out immediately to a mental health provider or emergency services. WHO specifically advises that people with suicidal thoughts talk to someone they trust or a health worker, and if in immediate danger, to contact emergency services or a crisis hotline [1]. Remember, depression is a treatable medical condition, and help is available. Early intervention with therapy, medication, or support can greatly improve outcomes.

Help Line: Should you notice signs and symptoms of depression in yourself or others, do not hesitate to seek for assistance. Treatment is FREE at Arogi Trauma Care Foundation. Just call the Toll-Free line 080-000-1-000-20 (Nigeria Only) or you visit us at our physical location at No 9, Olayeni Abiola Street, Off Salvation, Opebi-Ikeja, Lagos State, Nigeria.

Adedeji Odusanya

Odusanya Adedeji A., is a Licensed & Certified Clinical Psychologist whose domain of expertise cuts across management of specific mental health issues such as, Depression, PTSD, Anxiety & Anxiety related disorders, Substance Use Disorder, etc