Why SAD affects us in the winter

Seasonal Affective Disorder (SAD) is a state of depression that stems from the changing of the season, specifically – the summer to winter. In the winter, the days get shorter, it is cloudy and cold – but SAD isn’t a prophetic fallacy – it’s a physical reaction to a lack of vitamin D. Although there is a myriad of reasons as to how this depressive state can be triggered, none is more widely accepted than the vitamin D deficiency the body undergoes during the winter. A lack of vitamin D will create a chain reaction with other symptoms of SAD, which then feed into other depressive behaviours, in turn worsening the state of affairs. Let’s look at what vitamin D deficiency does to the human body.

Vitamin D, like all vitamins, it is a nutrient we make in our body; and most it comes from the sun. But vitamin D is unique as it is a hormone and not a nutrient like other vitamins. It works with calcium and phosphorus to create and maintain healthy bones, muscles, and teeth. Without enough vitamin D, your body will not be able to absorb calcium and other important nutrients that allow our body to function. In turn, many people with low levels of vitamin D will experience rickets, osteomalacia alongside other muscle and bone deficiencies. This leads us to be being tired, frustrated that our bodies are not functioning as it should be, and possibly lowering our immune system.

Vitamin D also has a role in maintaining stable brain hormones. Serotonin, the hormone associated with happiness, rises with the exposure to bright light – and drops in correlation with decreased sun exposure. As understood by research in medical science, people with lower vitamin D are 11 times more prone to be depressed than those with healthy does. A low level of vitamin D will cause a deficiency in serotonin, causing depressive-like behaviours to occur.

If we amalgamate these two factors, we see instantly that low vitamin D, caused by reduced sun exposure, is responsible for making us tired and unhappy. These physical deprivations feed into mental manifestations of psychological dispositions – such as bipolar – or other types of depression. It also suppresses the immune system, which can have a knock-on effect on making us ill, and then beginning the “cycle of depression”.

If you would like to learn more about how the cycle of depression works, click here.

SAD can have an extremely negative impact on your quality of life. If you need a consultation or are suffering from any of the symptoms outlined at the end of the article, please contact us on (212) 241-6321 to book an appointment.