Professor Anne Farmer, consultant psychiatrist
"Half an hour to an hour under a 10,000 lux 'daylight lamp' every morning from September or October to March or April, can really help, especially for people who are 'larks' who are usually brighter first thing in the morning.
"'Owls', people who perk up at night may find early evening more helpful. It's important to stay under the lamp for the required length of time and not to keep getting up and down.
"Antidepressants can help some either with light therapy or on their own. Depending on severity I might also prescribe Prozac or another SSRI.
"A serotonin and noradrenaline reuptake inhibitor such as venlafaxine, a drug that creates both more of both hormones can help increase alertness and energy as well as tackling the depression."
Marilyn Glenville, nutritional therapist
"An underactive thyroid can up the risk of depression and women are prone to this, especially as they get older so I'd encourage patients to get a thyroid test.
"Peaks and dips in blood sugar can exacerbate symptoms so I would advise cutting out caffeine, and unrefined foods like white bread, biscuits, pastries and cakes. I advise them to eat little and often.
"Chromium, found in foods like seafood, liver and fresh fruit and vegetables, helps combat carb cravings, which are a feature of winter depression. B complex vitamins found in foods such as oats, barley, avocado, salmon and Brazil nuts can help balance the nerves.
"I would also recommend supplements: a good multi-vitamin and mineral plus 25 mgs of B complex vitamins, 1000 mg of Omega 3s and 100 mcg of chromium which helps reduce sugar cravings.
"Exercise is an essential part of the plan - I would suggest going out for a brisk half hour walk at the lightest time of day."
Cognitive behaviour therapy
Linda Blair, psychotherapist
"Cognitive behaviour therapy doesn't take away the symptoms of SAD but it can help patients to accept and manage them better.
"When you learn how to see SAD as just a part of your life it gives you choices. I would recommend behavioural changes such as using a daylight alarm clock that emits increasing light levels to simulate the arrival of dawn as you gradually wake up and regular aerobic exercise to encourage the body to produce endorphins, its own feel-good hormones.
"It is important to give yourself the chance to cut down on stress at this time of year, so I would advise putting a sticker in your diary to remind you to go easier on yourself.
"It's a good idea to make a list of things that make you feel better such as phoning a friend or relative and keeping this in several different places, so you have a kind of mental toolkit to call on when you feel down. And of course if you can afford it take a holiday somewhere sunny."
Be aware of your diet
Penny Povey, naturopath
"A good diet is vital. Start the day with porridge. For lunch I would advise a bowl of vegetable soup or big salad with fish or turkey; for supper eat a handful of protein - again things like fish and turkey, - and some complex carbohydrates that help calm anxiety, something like brown rice and cooked veg. It's important to get some exercise - and fresh air.
"Herbs can be useful as an alternative to anti-depressants. Licorice helps tonify the adrenal glands, which are often involved in depression. Oat straw is also good for the nervous system. St John's Wort is good for mild to moderate depression and the herb Rodeola can help combat stress. Siberian ginseng helps to strengthen the adrenals and balances the system generally."
Phil Edmonds, registered homeopath
"The homeopathic remedy sepia can be good for depression that is made better by the sun, especially when the person is feeling overwhelmed, overworked and alone.
"Pulsatilla can help when the person is weepy and emotional but feels better when comforted. Nat Mur is good for grief that is linked to the past, while for really severe cases I might choose Aurum, especially for people who are perfectionists."