Have you ever wondered why some people find themselves confronted with depression correlated with specific seasons—known as Seasonal Affective Disorder (SAD)—and others don’t? Commonly occurring in fall and winter, this phenomenon is particularly curious since it can affect people that report feeling happy and emotionally satisfied in other seasons. New research suggests that the colour of your eyes may be a factor contributing to your susceptibility to Seasonal Affective Disorder.
One hypothesis is that the latitude distance a person lives from the equator is correlated to the degree that their mood varies with different seasons, however recent research suggests that there may be more to it. A study published in the Open Access Journal of Behavioural Science & Psychology suggests that latitude has no significant impact on an individual’s experience of seasonal mood variation. Instead, they found that eye colour had a significant impact, with blue/light eyed individuals reporting seasonal changes having a lower impact on their mood, weight, appetite, sleep and social activity. Their research went on to suggest that the amount of light an individual’s eye can process may be the reason why eye colour makes some people more susceptible to Seasonal Affective Disorder.
Light-eyed individuals require less light to process images, which also means that they produce less melatonin during fall and winter; the hormone produced by our bodies to help us fall asleep. Some experts believe that too much melatonin or an imbalance of melatonin and serotonin can contribute to feelings of depression. This would explain why light eyed individuals who produce less melatonin may be more resilient to Seasonal Affective Disorder, albeit not immune to it.
While this study poses interesting and compelling evidence that eye colour may influence SAD risk, it’s not the only factor that determines whether a person will experience it. If you believe you may be experiencing Seasonal Affective Disorder taking a break from fluorescent lights to spend some time outdoors is a proven way to uplift your mood. Natural light boosts serotonin levels, which can help address a melatonin imbalance that could be contributing to feeling depressed or lethargic. Light therapy with light boxes (especially in the morning) and regular exercise are also effective ways to restore the hormonal balance and help you feel better. Taking proactive steps to care for your mental health is important, and you should never be afraid to supplement your efforts by seeking additional support and guidance from your doctor.
To learn more about eye health and stay up-to-date on new research visit FYidoctors’ blog.