Lewis Wolpert is a scientist and sufferer. In Malignant Sadness: The Anatomy Of Depression, he likens depression to cancer - a normal function that spirals out of control. It is useful to realise that life is a pile of dung but unhelpful to believe you are at the bottom of it.
But Wolpert's exploration is strictly chemical and genetic. For a far more beardy view, turn to The Wisdom of Depression by Dr Jonathan Zeuss, published last week. His take is that instead of suppressing the symptoms, we should discover what our body is saying to us.
I wrote last year about a Newcastle psychologist who held the controversial view that anti-depressant dispensers should be placed next to the condom machines in pub toilets (well that's practically what he said) - that dung, in other words, is natural, but in our stress-filled E-numbered 20th century we need chemicals to restore the balance. Dr Zeuss agrees that modern life is unnatural but says there are many holistic options before you have to turn to drugs, especially since depression covers everything from despair to feeling a bit blue.
Dr Zeuss's advice is highly practical. Psychiatry may refute it but studies have shown that depression can be linked to vitamin B deficiency. One study, says Dr Zeuss, found that 53 per cent of psychiatric patients were deficient in vitamins B1, B2 and B6. So try a supplement and eat wholemeal grain and cereals. Or are you a vegetarian female on a diet? And depressed? Check out your iron levels before you reach for the Prozac. If the base of your fingernails or eyelids are pale, you may be anaemic. Eat offal. Vegetarians, take vitamin C with your watercress to aid absorption. Avoid sugar but not chocolate which is "thought to have anti-depressant effects".
Zeuss also covers light, sleep and self-healing. Even wearing sunglasses might lead to depression. (Now we know why celebrities are so moody.) And for those who favour complementary medicine, there's St John's Wort, components of which "cause a change in the number of serotonin receptors in the brain cells, much as does Prozac".
Dr Zeuss does, however, overlook that oft-forgotten victim of depression - the people forced to listen to their depressed mates. If you feel yourself being sucked under, here's my own suggestion: the "misunderstanding approach". A friend was despairing to a work colleague. "Oh, what's the point?" he said. To which the deliciously uncomprehending colleague replied: "A multiplex cinema in Reading". And walked off. My depressed friend laughed so much he felt better.
What to do if you're depressed:
1. Go to your GP first to establish if misery is endogenous (either biological, hormonal, etc) or reactive to circumstance.
2. Is it habitual, a learned reaction that you can unlearn with the help of a counsellor?
3. Do you have good reason to be depressed - unemployment, loneliness, etc? Small practical steps may help. Seek out positive activities - friends, a career counsellor, exercise.
4. Look at how and when you get into a bad mood. Being aware of your cycles will help to prevent them. One group of therapists banished Sunday blues by spending every Monday morning playing golf. It worked.