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SAD lamps: do you really need one and how to buy the best

Seasonal affective disorder symptoms, recommended treatments and how to choose a SAD lamp
Martha RobertsSenior content writer

As the nights start drawing in, you may be considering a light box to boost mood and banish the winter blues - but is it the best solution for you?

We explain what seasonal affective disorder (SAD) symptoms look like and the treatments available, plus we give you tips for choosing a SAD lamp to suit your needs.


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What are the symptoms of SAD?

Someone lying in bed in the morning, looking like they're having trouble waking up.

Around three in every 100 people in the UK suffer from SAD - a significant seasonal depression that can have a big impact on their daily lives and whose symptoms include:

  • Sleeping more. Unlike those with non-seasonal depression, you might find yourself sleeping more and having trouble getting up.
  • Eating more. You may crave carbohydrate-rich and sweet foods, which can lead to weight gain.
  • Social withdrawal. Avoiding family and friends and withdrawing from social activities you normally enjoy can be a sign of SAD.
  • Depression at specific times of the year. It tends to happen in autumn and winter and is sometimes known as 'winter depression', although around 10% of people with SAD get it during the spring and summer instead. 
  • At least two consecutive years of SAD episodes. These are followed by feeling completely better when the winter season is over, only for symptoms to return the following year - something experienced by around two-thirds of sufferers.

SAD can replicate depression in various ways including persistent low mood and lack of interest and enjoyment in life, but it's these additional symptoms that help to differentiate it.

Causes of SAD

The exact causes of SAD aren’t entirely clear but research suggests a few things may contribute to its development, including:

  • High melatonin levels. This hormone is produced by the brain to make us feel sleepy when it's dark but it's thought that people with winter SAD have too much of it and therefore feel sleepy during the day, too.
  • Low serotonin levels. The so-called 'feel-good' hormone has been found in lower levels than normal in the winter in people who get SAD, according to research at Copenhagen University Hospital.
  • Body clock disruption. Our bodies use sunlight to regulate various functions, including when we wake up, so it’s thought that reduced light in winter may disrupt our internal body clock, including our sleep patterns/phases so it's out of sync with other people.

It can develop at any age but generally starts between the ages of 18 to 30, may be hereditary and is more common in women and those who live near the equator for part of their lives before moving further away.

Research by Professor Lance Workman at the University of South Wales suggests that having dark eyes may be a risk factor, too - one theory is that light-coloured eyes let in more light needed to activate retinal cells to normalise melatonin levels. 

What are the treatments for SAD?

A family enjoying some time in bright sunlight by the coast.

The Royal College of Psychiatrists (RCP) says self-help measures will usually be enough to ease it, even in people who have it severely. Here's how:

  • Spend time outside. ‘This is probably the most important point, since SAD is caused by lack of daylight,’ says Professor Workman. Outdoor exercise such as cycling, walking or running may help, especially in the morning.
  • Try light therapy. The average daily dose is 1-2 hours of very bright light that's at least 10,000 lux (or lx, the units that visible light is measured in) - around 10 times the intensity of ordinary domestic lighting.
  • Meet up with friends. Combat the temptation to cut yourself off by finding reasons to socialise, for example through group sports or exercise classes, especially as exercise has been shown to improve SAD symptoms.
  • See your GP. They may recommend cognitive behavioural therapy (CBT) or a seasonal dose of SSRI (selective serotonin reuptake inhibitor) antidepressants such as sertraline or citalopram, and if your SAD recurs then long-term or preventative treatment with the antidepressant bupropion may help.

Managing stress levels can be hard. Consider trying mindfulness apps or accessing counselling services.


What is the evidence for SAD lamps?

An older woman with grey hair, looking at a light box while holding a book.

In 2019, Cochrane – a global independent research network whose reviews are considered the gold standard for research – evaluated existing data on light therapy for SAD and concluded that the quality of evidence about whether it prevents winter depression is very low. 

Mental health charity Mind says: ‘The NHS doesn’t provide light therapy because there is currently insufficient evidence to show it works, although some people find it helpful.’

Some studies have found it’s an effective treatment during a SAD phase in up to 85% of diagnosed cases, especially if used first thing in the morning, and those who it helps notice symptom improvements within a week or so.

It’s thought that light therapy is best for producing short-term results, which means it may help relieve your symptoms when they occur, but you might still be affected by SAD the following winter.

You can find out more on the NHS guide to SAD treatments.


Why is it so hard to get a GP appointment? We look at how to get help when you need it


6 tips for buying the best SAD lamp

A young woman reading a book with a SAD lamp nearby.

If you want to try a SAD lamp, they're available from retailers including Amazon, John Lewis, Argos and Boots or you can search online where there are a number of specialist retailers. 

Before you buy, read through our tips for getting the best one for you:

1. Check you can use a SAD lamp 

Although most people can use light therapy safely and reputable light boxes have filters to remove any harmful UV rays, you may want to check with your GP or pharmacist before use as exposure to very bright light isn’t suitable for everyone, including:

  • Those with eye damage or a light-sensitive eye condition such as age-related macular degeneration. 
  • If you take medication that increases sensitivity to light such as certain antibiotics and antipsychotics. 
  • If you take herbal supplement St John’s wort, which is sometimes used to treat mild to moderate depression. 
  • Those with skin condition lupus erythematosus, which makes skin especially sensitive to light.
  • Those with bipolar affective disorder as light therapy may trigger some patients.

Side-effects of light boxes may include headaches, nausea and blurred vision, but the RCP says these tend to be mild.

2. Choose a SAD light that’s properly registered

SAD light brands include Beurer, Lifemax, Lumie and Philips.

Check that your purchase is a 'medical device' that’s registered with the Medicines & Healthcare Products Regulatory Agency (MHRA) -  this will be stated on the box or on the product's website or contact the manufacturer.

Do NOT use sunlamps, tanning lamps or halogen lamps as these may cause you harm, and don't bother with blue or bluish SAD lamps as there's no known advantage over bright white ones.

Dismiss any claims that SAD lamps boost vitamin D - they don't. 

3. Get a SAD lamp that's strong enough

Two adults with their children at a breakfast table.

You need a bright light emitting at least 2,500lx and preferably 10,000lx to benefit from the effects, with research suggesting a dose of 5,000lx hours a day (equating to 10,000lx for 30 minutes a day) at around 40cm from the unit.

However, the light intensity and duration of treatment will depend upon your device and your response to it – you may find that as little as 2,500lx works for you.  

Light from a SAD lamp is safe for use during pregnancy and it's also safe for children to be exposed to.

4. Buy a SAD lamp to suit your lifestyle

Someone using a yellow Lumie Task SAD lamp.

There are plenty of styles to choose from including portable ones, like the Lifemax SAD therapy light (Amazon, £46.95) or the Beurer TL30 Portable Daylight/SAD Lamp (Boots, £64.99).

If you want a lamp to fit in with your decor, the Lumie Task SAD light therapy desk lamp (John Lewis, £249) comes in five colours.

SAD lamps can cost up to several hundred pounds so you may be tempted to buy a basic model with fewer features, but if doesn't fit in with your lifestyle it may be more difficult to commit to regularly using it.

Ask yourself whether you need extra features such as a timer that switches it on as a reminder or hangs on a wall in front of you while you're working out on your home exercise equipment.

5. Use a sunrise alarm clock

A woman looking at a sunrise alarm clock next to her bed.

Also known as light alarm clocks or dawn-simulating alarm clocks, these slowly increase light in the room for the 90 minutes leading up to the time you want to wake up. 

Some mimic the colours of a real sunrise and feature natural birdsong sounds, such as the Philips Wake Up Light (Amazon, £94.99).

The RCP says sunrise alarm clocks may be beneficial if you struggle to wake on winter mornings, helping to gently reset your body clock.

However, the light isn't as strong as SAD lamps so although they can be used in conjunction with them, they're not a medical device and won't have the same effect if used on their own.  

6. Try a SAD lamp before you buy

Some manufacturers allow you to try a SAD lamp for a period of time before you buy, such as Lumie, which offers customers a 45-day trial.

The other alternative is to consider hiring or renting one to see if it works for you. 

If you do buy one, SADA recommends replacing bulbs every three years, so it’s important to factor in the cost of replacements.


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How to use a SAD lamp: step-by-step guide

A woman holding a mug and sitting in front of a SAD lamp.

Before you use your lamp, read the instructions for your specific product, including how far away it should be from you and how long you can use it for, but here's some general guidance for use:

  • Use early in the morning. The RCP advises using your lamp at breakfast time to help regulate the circadian pattern of melatonin secretion, and you should avoid exposure close to bedtime as it could disrupt your sleep.
  • Sit the correct distance from it. Standard guidance is 40cm or arm's length away but check the instructions for your specific product, both in terms of distance and how many minutes you need to use it for.
  • Keep your eyes open while it's on. You don't have to stare at it and can watch TV, work or even use home gym equipment while you're using it but the light from the box must reach your eyes for it to have any effect.
  • Use it every day, including weekends. Carry on through the darker months until the days get longer in the spring and summer. It's safe to increase your exposure each day until you find a length of time that suits you.