NOTE: All blog postings on the AFWC website are intended for purely educational purposes and not as personalized medical advice. We advise you to speak with a healthcare professional before making any health or lifestyle decisions.
We Alaskans know how precious the long days are in the summer and live them to the fullest. It has been a cool and rainy one this year but still the days have been long. This time is short-lived, however, as September rolls forward with the return of kids to school and cold weather, the grasses and cow parsnips are turning from green to yellow.
Many Alaskans look forward to the shortening of the days, the falling of the light and eventually the arrival of snow and cold. Others have a very hard time with the Dark Seasons. For some this may be due to Seasonal Affective Disorder (SAD). Simply stated, SAD involves the accumulation of too much of the sleep neurotransmitter, melatonin, in the brain due to the low light conditions of winter time. In excess, melatonin makes us tired, promotes craving for carbohydrates and can even cause depression. The brain is designed to accumulate melatonin as the dark of evening sets on to put us to sleep and rest at night. Then, as the sun comes up and shines on the sleeper then the melatonin production stops, levels fall and the sleeper awakens.
Our modern lifestyles involving artificial lighting and hours of awakeness that don’t correspond to the light cycle predispose us to problems. This is markedly exacerbated with the extreme low lighting associated with the high latitudes of Alaska(“It’s dark when I go to work and dark when I go home!”) along with the cloudy skies prevalent here.
Some people are more sensitive than others. Some people have no problem with the low light and even prefer it. Others may become mildly irritable while others have difficulty functioning. This is a reminder of how unique we are, each a symphony of genetics, lifestyles, behaviors and life circumstances put together of make up our experiences.
There are many ways of avoiding the issues of SAD. The first step involves recognition of the problem. There is a questionnaire we use that identifies the patterns of SAD and depression. Second is to find ways to reduce levels of melatonin.
SAD lights have been developed for a simple approach. These are lamps that use a fluorescent bulb that generates 10,000 lux (a measure for light brightness and 10,000 lux is really, really, really bright!) It is important to have a layer of plastic between the light bulb and your eyes as the bulb produces ultraviolet light which is bad news for your eyes, the plastic absorbs that light. Light brightness falls of using the rule 1/s squared, i.e., twice the distance away from the light source the light is 1/4th as bright so how close you sit is important. When you use the light is also important. I generally tell people to use the light first thing in the morning for 30-60 minutes.
Getting outside during the middle of the day to get fresh air and a little exercise is also very helpful. You will hear from me many times, diet is a cornerstone for all health. In this case, avoiding processed foods and especially sweets ( sugar is a “psychoactive substance”) is key.
SAD is most effectively treated with the light if you start early. We generally suggest patients start now- early September- to avoid the accumulation of levels of melatonin. It can be difficult to catch up once you get behind.
Vitamin D is also associated with light exposure and has an effect on mood but that is not affected by SAD lights and taking vitamin D won’t reduce melatonin levels. More on vitamin D in a later blog.
A final important thought: SAD doesn’t always fully respond to the SAD Light and it can look like other forms of depression. Depression can be an extremely serious, even life threatening disease if not addressed appropriately. So, if you have concerns about SAD or depression, please see a competent clinician who can help you find answers to your concerns.
To Your Health!