Affecting at least 1 in 20 people, Seasonal Affective Disorder (SAD) is a specific type of depression that occurs generally during the dark winter months. Caused by a lack of natural light, SAD is most prevalent during the October to February period in countries such as the UK where there is far fewer hours of daylight and a heavy reliance upon artificial lighting (i.e. those that live the furthest away from the equator).
Experts believe that this lack of light is overwhelmingly the primary cause of SAD as the amount of sunlight that hits our eyes directly affects the levels of certain chemicals and hormones in our brain.
Symptoms of SAD
Millions and millions of people struggle through the cold winter months without even knowing that they have SAD. According to SADA (The Seasonal Affective Disorder Association of the UK) symptoms include:
- Sleep problems
Anxiety & lowered tolerance to stress
Loss of libido
Personally, I can immediately think of a couple of people I know who suffer these symptoms during the winter months and the chances are that you can too. So how does SAD occur and what can we do to combat it?
Seasonal Affective Disorder and our Dependancy on Sunlight
As discussed, SAD is primarily caused by a lack of sunlight affecting the balance and production of certain hormones and chemicals in the brain. To understand how something as simple as this could have such an affect on our mental wellbeing it is important to consider how much sunlight we actually receive from different sources.
Light is measured in units of lux – which is defined as roughly being:
The amount of visible light per square meter incident on a surface.
It is roughly accepted that one lux is equal to the illuminance provided by an ordinary wax candle (more definitions here).
To put this into context the lux provided to our eyes by a normal sunny day is approximately 100,000 lux, whereas a normal lightbulb or desk lamp provides just 300-500 lux.
When you look at it like this it is easy to see how this can have such a harsh effect on our mental health. Especially when you consider how many of us wake up in the dark, drive to work in the dark, sit in artificial light all day, and then drive home in the dark etc.
So What Effect Does the Lack of Lux Have?
In essence, the amount of sunlight we receive controls two key chemicals in the brain, melatonin and seratonin. According to BUPA.co.uk:
- serotonin plays a role in ‘lifting’ mood. It is thought that people with SAD may have abnormally low levels of chemicals such as serotonin in winter.
- melatonin slows down the body clock, and affects sleeping and mood patterns.
During the low-light winter months the imbalance of the production of these chemicals creates abnormalities in the way that our body manages its biological rhythms. As melatonin is produced largely during the darker hours and serotonin during the lighter hours there becomes a huge imbalance in how the body performs throughout the day and night.
People with SAD are generally those that produce far more melatonin than serotonin and far more than is required, leading to many of the symptoms above. As many of you will no doubt be aware, the production melatonin is also key in stabalising our internal body clock which explains the symptoms such as lethargy, unrestful sleep, low energy and anxiety and certainly compounds the symptoms such as stress tolerance, diet, socialability, loss of libido etc.
How Can I Combat Seasonal Affective Disorder?
The first thing you need to do is visit your doctor or speak to someone who is medically qualified to deal with these types of problems. However, there are several steps you can also take which have been shown to have a remarkable effect on the symptoms of SAD:
- Light Therapy
According to the NHS, research studies have shown that light therapy can greatly improve symptoms in about 2 in 3 cases of SAD. Light therapy (discussed in great detail here) involves an individual sitting at a recommended distance from a fluorescent light box which produces a light intensity of between 2500 and 10000 lux.
Light therapy combats SAD by exposing the eyes to intense light. When the light hits the retina the light is transmitted by nerve impulses to the pineal gland which is responsible for melatonin secretion. This function can help moderate the body’s internal clock, also known as the circadian rhythm. Light therapy is also able to reduce the daytime melatonin levels, while also enhancing the effectiveness of serotonin and other neuro-transmitters – which explains its ability to be able to effectively treat seasonal affective disorder.
I have personally used light therapy to combat jet-lag on more than one occasion (including right now as I type) and others I know have also had great success in treating SAD with this treatment. However, it is still recommended that you speak to your Doctor about your symptoms before you start any form of self treatment. (click here for light therapy products)
- Increasing Exposure to Natural Sunlight
As an alterative to, or alongside light therapy, increasing exposure to natural light can obviously have a great effect on SAD symptoms. This is particularly important to those who work in an office environment where most of the scant light winter hours are spent indoors. Try to find time to exercise outdoors every day – even if this only equates to an hour long walk at lunch time. While this is obviously dependent upon the weather, even just one hour outside during the day can have a huge impact upon SAD.
- Physical Activity
Related to this is exercise, as this can have a great effect on the body’s ability to function properly and can also assist with the sleep and energy problems related to SAD. Try to do at least 30-60 minutes of aerobic exercise at least 3 times per week.
What we feed our bodies can also either increase or decrease the effects of SAD. By giving your body fresh, nutrient dense foods you are arming it with all of the tools it needs to work as effectively and efficiently as possible. Diet has been inextricably linked to mood, sleep, anxiety and depression so it is wise not to further compound any symptoms that may be showing. Of particular importance are omega oils, so if you do not eat fish, flax seeds or other sources of omega 3, consider supplementation.
It is clear that SAD can be treated both naturally and inexpensively, however, DO speak to your doctor as there may be other underlying causes of these symptoms and self-diagnosis is not always the most accurate.
Further Sources of Information