Because I am British, it probably comes as no surprise that I unequivocally understand the heartbreak of traditional rainy weather. An indestructible stereotype of the UK, bad weather has never really manifested the ability to catalyse happiness during the morning commute. Whilst the occasionally odd shower is often welcomed, consistent wind and rain provokes noticeable negativity in people – have you ever been in central London during commuting hours? Yikes. Why then, for many of us, does our mood shift in association with the weather? Interestingly, science may have the answer! This discussion is dedicated to what has been coined seasonal affective disorder. Here I will survey some of the evidence surrounding the condition and describe what we may be able to do to fight back against it!

Seasonal affective disorder: what exactly is it?

Seasonal affective disorder is a form of depression otherwise referred to as SAD or seasonal depression. As you may have guessed, people who suffer with SAD tend to experience mood changes and symptoms similar to depression. These symptoms appear to correlate with the changing seasons, primarily beginning in the autumn and winter months, before alleviating during the arrival of spring. With this in mind, it is important to note that SAD is more than just “winter blues”. The symptoms can be distressing, debilitating, and can significantly interfere with daily functioning. Nevertheless, various treatment options are available.

Causes

Unfortunately, the biological cause(s) of SAD is still relatively unknown. However, some evidence suggests that it is related to the body’s level of melatonin, a hormone secreted by the pineal gland. Melatonin regulates the sleep-wake cycle, and darkness is known to stimulate its production, preparing the body for sleep. Because more melatonin is therefore produced during the winter months (when sunlight hours are diminished), people tend to feel sleepier and more lethargic. 

In addition, research suggests that some people who develop SAD may produce less Vitamin D. Interestingly, Vitamin D has been suggested to play a role in serotonin activity, a key mood regulating neurotransmitter which is reduced in some depressed patients. 

Treatments

Interestingly, human clinical trials have identified that both cognitive behavioural (e.g. talk) and light therapy improve the symptoms of SAD, wherein the latter may be more effective for reducing four key signs of the disorder: early insomnia, anxiety, hypersomnia, and social withdrawal. So, if you needed a sensible reason for an expensive winter holiday to the Bahamas… you are most certainly welcome. However, more practical approaches to tackling SAD symptoms include taking care of your general health and wellness, which involves (yep, you guessed it…) regular exercise, good nutrition and getting enough sleep. Spending time outside and rearranging your office space so that you are exposed to a window during the day may also be of benefit.

Does blindness contribute?

From a scientific perspective, there are many interesting questions arising from SAD research. For example, is it more common in people with serious visual impairment? Does the likelihood of developing SAD increase as eyesight progressively degenerates? What about people who are blind and have been since birth; do they develop symptoms of SAD? These are all interesting research avenues which are currently being investigated.

It is important to seek help

Whilst it is thought-provoking topic to discuss, please remember that If you feel like you or a loved one has experienced depressive symptoms for an extended period of time, contact your nearest doctor for support.