14.2 — Depression

Not sadness. Sadness has an object and responds to comfort (4.2). Depression frequently has neither.

The two core features, and at least one has to be present most of the day, nearly every day, for at least two weeks:

Persistent low mood, or loss of interest and pleasure in things that used to matter.

That second one is the more distinctive. Sadness with intact interest is grief. Not wanting anything is depression.

Alongside, some of: sleep disturbance — too little or too much, and classically waking early and not getting back; appetite and weight change; fatigue; slowed movement or agitation; difficulty concentrating and deciding; worthlessness or excessive guilt; and thoughts of death or of not wanting to be here.

What it actually feels like

Because the checklist misses it.

Flatness rather than sadness. Many people describe an absence rather than a pain. Nothing is interesting. Nothing is worth the effort.

Everything is heavy. Ordinary tasks — a shower, a phone call, an email — feel as though they require enormous effort, and this is not a metaphor.

Thinking is slow and foggy. Memory and concentration genuinely degrade.

And the reasoning feels correct. This is the cruellest feature. The thoughts — I am useless, this will not improve, everybody would be better off — do not feel like symptoms. They feel like finally seeing clearly. They are produced by the state and they will change when the state does, and from inside that is impossible to believe.

In men and in many cultures it frequently presents as irritability rather than as sadness, and as physical symptoms — pain, fatigue, stomach problems. In India and much of South Asia the physical presentation is common, and it means depression is frequently treated as a physical complaint for years.

What causes it

Not a serotonin shortage. The chemical imbalance story was never established and a major review found no consistent evidence for it. This does not mean antidepressants do not work — a drug can help without the original theory being right, exactly as paracetamol works without a paracetamol deficiency.

What the evidence supports: genetic vulnerability, early adversity (13.10), current stressors — particularly loss, humiliation and entrapment — chronic stress (6.5), physical illness, some medications, and sleep disruption (2.8).

And two psychological mechanisms with good support. Rumination — the strongest predictor in the psychological literature (5.5). And withdrawal, which removes the sources of reward and produces the spiral below.

The spiral

Understanding this is what makes the treatment make sense.

You feel flat, so you do less. Doing less removes the small rewards that maintained mood. With less input, you feel worse. So you do even less.

Meanwhile the thinking turns inward, the ruminating produces more low mood, and the low mood makes the negative material more available (2.5).

Both loops are self-sustaining, and both are interruptible from the behaviour end.

What works

Behavioural activation. Scheduling activity regardless of motivation (8.8). Simple, unglamorous, and it performs comparably to cognitive therapy and to medication in trials. It works by attacking the withdrawal loop directly.

Cognitive behavioural therapy (15.3). Well established. Targets the thinking and the behaviour.

Antidepressants. Effective, particularly for moderate to severe depression, where the benefit over placebo is clearest. For mild depression the advantage is smaller and therapy is usually preferred. They take two to six weeks to work, the first one tried does not always suit, side effects are common early and frequently settle, and stopping suddenly causes discontinuation symptoms — taper with a doctor.

Exercise. Real effects, moderate size, and one of the few things that acts on both the psychological and the physiological side (6.8).

Treating the sleep (2.8). Treating insomnia improves depression, sometimes substantially.

And for recurrent depression, mindfulness-based cognitive therapy has good evidence for preventing relapse (7.2).

Combination beats either alone for moderate to severe presentations.

What does not work

Waiting for motivation (8.8). Motivation returns after activity, not before.

Being told to cheer up, to be grateful, or that others have it worse.

Alcohol, which is a depressant and worsens sleep.

Withdrawal, which is the mechanism.

And self-criticism about being depressed, which adds shame to the load (4.8).

If it is you

Do one small thing today, chosen in advance rather than when you feel like it. The smallest version (8.8).

Get outside and move, however briefly. Light and movement, and both act on this.

Tell one person the actual truth.

Book the appointment. GP first is fine. Say the plain sentence: "I think I might be depressed." That is enough to start.

Do not make large decisions — quitting, ending relationships, moving. Depression distorts assessment in a known direction and the decisions will look different afterwards.

And if you are having thoughts of ending your life, go to 14.8 now. In India: Tele-MANAS on 14416, free and 24 hours.

If it is somebody else

Do not try to argue them out of it. The thoughts are symptoms, not positions, and debating them fails.

Do specific things rather than offering. "I'm coming at six and we're walking to the shop" works. "Let me know if you need anything" does not, because initiating is the thing they cannot currently do.

Keep showing up after everybody else stops (4.7).

Help with the practical steps — booking the appointment, going with them.

And ask directly about suicide if you are worried. "Are you thinking about ending your life?" Asking does not plant the idea — that is a myth, and the evidence is against it. Asking gives permission to answer (14.8).

What to do

Apply the two-week, two-core-symptom test honestly.

Check the physical first — thyroid, iron, B12, vitamin D, sleep, alcohol, medications.

Start with behaviour rather than with feeling. One small scheduled thing, daily, regardless of mood.

And get an assessment. Depression is common, treatable, and the outcomes are considerably better with treatment than without. The main thing that determines how long it lasts is how long before somebody helps.

Next: 14.3 covers the anxiety conditions, which are the most treatable set in this Part and among the most under-treated.