Tag Archives: sad light box

Light therapy & SAD: Look on the Bright Side

Could Light Therapy help beat your winter blues?

While many look forward to the crisp and clear autumn and winter months, others find that they struggle through these months feeling tired and low. Seasonal Affective Disorder, also known as SAD, is a form of depression that is brought on when levels of natural sunlight are reduced. Symptoms tend to begin as the days get shorter and winter draws in, only lifting completely during the summer months. A milder form of seasonal depression – often called sub-syndromal SAD (S-SAD) or simply ‘the winter blues’ – affects around 1 in 10 adults.

Bright Light Therapy
SAD is a form of depression that is brought on when levels of natural sunlight are reduced

I was interested to read a recent Swedish study that tested a treatment called ‘bright light therapy’ on individuals with SAD and with S-SAD (1). Bright light therapy is a treatment that involves exposure to a special light that mimics natural outdoor light.

The study tested the effects of the light therapy on 49 individuals who had been diagnosed with either SAD or S-SAD.

When the individuals began to experience winter depressive symptoms, some of the group were either given a 10-day course of bright light therapy, or were put onto a 3-week waiting list, after which they were given the 10-day treatment course. The group of people on the waiting list were used as the ‘control’ group for this study.

The study found that bright light therapy was linked to improvements in a number of symptoms. The researchers had conducted an earlier randomised clinical trial which found that bright light therapy did indeed have a positive effect on depressive mood in those with SAD and S-SAD (2). This new study, however, also measured the effects of bright light therapy on other symptoms, such as tiredness, fatigue, sleep problems and health-related quality of life. All of these symptoms had improved after the 10-day course of light therapy. Symptoms were then measured again, a month after the treatment had finished, and it was found that the symptom improvements had lasted.

The study suffers because, although a control group was used, strictly speaking there was no placebo group. If the second group had been exposed to a ‘placebo’ light rather than the therapeutic bright light, then this might have served as a better comparison group. The study is nevertheless very interesting because it indicates that light therapy can help not just depressive mood, but that it can bring about improvement in a number of symptoms including milder symptoms of depression and daytime sleepiness.

Despite the design flaw in the study, light therapy does appear to be a promising treatment for the ‘winter blues’. Systematic reviews have reported that light therapy represents an effective and well-tolerated treatment for SAD (3). A home light box may therefore be a wise investment for those who need a boost during these darker months. Using a light box for between 30 minutes to an hour in the morning is considered to be an effective approach, and the light should be at least 2500 lux to be beneficial. Some individuals also use a Sunrise Alarm Clock as well to help balance their circadian rhythm and ensure they wake naturally in the morning rather than to the sharp, shrill noise of a standard alarm clock. These Wake-Up Lights simulate the “sunrise” so the brain wakes gradually.

Seasonal affective disorder, or the milder ‘winter blues’ can mean months of misery for those affected. With an estimated 1 in 20 adults affected by SAD, and a further 1 in 10 suffering from its milder form S-SAD, it is certainly an approach worth considering.

Written by Nadia Mason

1. Rastad C, et al. Improvement in Fatigue, Sleepiness, and Health-Related Quality of Life with Bright Light Treatment in Persons with Seasonal Affective Disorder and Subsyndromal SAD. Depression Research and Treatment. 2011:543906
2. Rastad C, Ulfberg J, Lindberg P. Light room therapy effective in mild forms of seasonal affective disorder—a randomised controlled study. Journal of Affective Disorders. 2008. 108(3):291–296.
3. Lee T M, Chan C C. Dose-response relationship of phototherapy for seasonal affective disorder: a meta-analysis. Acta Psychiatrica Scandinavica 2000. 99(5): 315-323


An Introduction to Seasonal Affective Disorder and the Winter Blues

About SAD

Seasonal Affective Disorder, or S.A.D., is now officially recognised as a medical condition thought to affect over 2 million of the British population.

SAD can affect people of any age but most commonly it starts between the ages of 18-30. At one time it was thought that four times as many women as men suffered from SAD, but now increasingly men recognise the symptoms and seek treatment. SAD is also known as the Winter Blues, and about 10% of the population suffer to some degree with 2-3% suffering with clinical depression.

Typical symptoms include:

  • Depression, feelings of gloom and despondency for no apparent reason.
  • Lethargy, lacking in energy, unable to carry out a normal routine.
  • Anxiety, inability to cope.
  • Social problems, irritability not wanting to see people.
  • Sleep problems, finding it hard to stay awake during the day, but having disturbed nights.
  • Loss of libido, not interested in sex or physical contact.
  • Craving for carbohydrates and sweet foods, leading to weight gain.
  • Recurring symptoms year after year at about the same time of year (Autumn / Winter).

The Cause

SAD has a lot in common with the hibernation cycle of animals and research showed that this was triggered by a response to decreasing light levels. As the days grow shorter and the light becomes less intense, it increases the desire to ‘hibernate’.

Light intensity is measured in ‘lux’ the Latin word for light. On a summer’s day at our latitude we may have up to 16 hours of daylight at 100,000 lux. In winter an 8 hour dull day will give less than 5,000 lux and indoor lighting rarely exceeds 500 lux.

The Treatment

Lights from trusted brands like the SAD Lightbox Co. have medical certifications and quality assurances.

Historically, treatment for depression involved the use of drugs, however, in recent years research in the USA and UK showed that SAD sufferers responded, often quite dramatically, to Bright Light Treatment. Fully proven lightboxes from trusted brands such as the SAD Lightbox Co. (carrying ISO 13485 / 9001 and Medical CE Mark 0120) have been specifically designed for and are a recognised method of alleviating S.A.D.

Lack of light causes an increase in the production of Melatonin (the hormone that makes us sleepy at night), and a reduction of Serotonin, a lack of which causes depression. The exposure to bright light therapy reverses the process, with the additional benefit of being drug free. You should start to feel the benefit within 4-10 days of using a lightbox.

By providing summertime levels of light during the winter you can successfully alleviate the symptoms of SAD with the result that former sufferers can lead a normal, happier life and beat the Winter Blues.

Studies have also shown that bright light therapy can prove beneficial with Pre-menstrual syndrome, Jet lag, shift work, insomnia and with some cases of MS and ME. The Light Therapy Institute have also been successful in treating children with dyslexia and specific learning difficulties; even children and students without these problems can benefit and work better by using the lightbox as a desk top working light.



Trouble getting up in the mornings? A new symptom linked to SAD.

At this time of year, many people struggle to get up in the dark mornings. The lack of light on winter mornings affects sleep-related hormones, leaving many tired and unrefreshed.

Trouble getting up in the mornings?
Those with DPSP have difficulty getting to sleep at night, and struggle with rising in the morning. (4)

A new study, published in the October issue of the Journal of Affective Disorders, has assessed individuals with symptoms of delayed-phase sleep phenomenon (DPSP) and has found links with SAD (1). In DPSP, the bodyclock’s natural cycle of sleep and wakefulness is altered, and the effect is similar to jet lag. As a result, those with DPSP have difficulty getting to sleep at night, and struggle with rising in the morning.

In the study, researchers assessed a group of 327 individuals with DPSP, and compared them to a group of 331 controls (individuals without DPSP). They found that those with DPSP were much more likely to have seasonal affective disorder (SAD).

The research also found that those with DPSP were more likely to experience changes in appetite, body weight and fatigue during the darker months – symptoms that are common in SAD.

The study concluded that both DPSP and SAD may have the same underlying cause.

One treatment that has shown positive results with both DPSP and SAD is dawn simulation therapy. Dawn simulators, or sunrise alarm clocks, are alarm clocks that use gradually increasing light to simulate the sunrise each morning. Light receptors in the retina can detect the light, even through closed eyes. This type of light therapy can be used to help ‘reset’ the body clock, making winter mornings less of a struggle.

A recent controlled study found that both light boxes and dawn simulator alarm clocks were effective in treating symptoms of SAD (2), while a recent review recommends light therapy to address DPSP (3). While standard light boxes are indeed useful in this regard, dawn simulators can be more convenient for many. Using a dawn simulator alarm means that you don’t have to set aside time each day for your light therapy. And so for those with DPSP or SAD, using a dawn simulator that works while you sleep may make winter mornings less of a struggle.

Written by Nadia Mason


1. Lee et al (2011) Delayed sleep phase syndrome is related to seasonal affective disorder. Journal of Affective Disorders 133(3):573-579

2. Terman & Terman (2006) Controlled trial of naturalistic dawn simulation and negative air ionization for seasonal affective disorder. Am J Psychiatry 163(12):2126-33.

3. Martinez & Lanz (2011) Circadian rhythm sleep disorders. Indian J Med Res 131: 141-149.

4. Image courtesy of Stuart Miles.