Does Light Hold the Key For Mental Health?
Could something as simple as exposure to light hold the key to protecting us from depression and anxiety and safeguard our mental health? The findings of a major recent study suggest it does.
Messing With Your Circadian Rhythm
First, let’s recap how our body reacts to light. Cells in our brain respond to light or dark in our environment by triggering hormonal changes. These hormonal signals activate a cascade of reactions in our body which affects almost every system in the body including the body’s temperature, our metabolism and whether we stay alert or wind down in preparation for sleep.
What happens when we expose those same light receptors in our brain to bright artificial light at night and/or limit exposure to natural daylight during waking hours? Simply put, it messes with our circadian rhythm and endangers out mental health.
Mental Health Risk
A study published in the October edition of the journal Nature Mental Health found that increased exposure to nighttime light is linked to an increased risk for major depressive disorder, generalized anxiety disorder, PTSD, psychosis, bipolar disorder, and self-harm behavior.
The impact of light exposure on depression alone was particularly striking: the study found the risk of depression was increased by 30% for high nighttime light exposure, whilst regular access to daytime light caused a reduction of depression risk of 20%. Combine the two and you have a 50% more chance of experiencing or preventing depression.
More Light in the Day, Less Light at Night
The principles are disarmingly simple: reduce light at night and seek light during the day.
Daily exposure to daylight is as simple as getting outside at some point in the day. Whilst indoor lighting may seem bright, our visual system recalibrates our perception to make it seem brighter than it is. Natural daylight is much brighter and it’s what’s required to trigger the needed biological effect. To maximize the effect of re-establishing a healthy circadian rhythm, aim to get outside first thing in the morning, try have your morning cuppa outside, go for a walk or potter in the garden.
We already know the benefits of avoiding screens in the hour or two before sleep, however, to maximise the benefits of reducing night time exposure to light, try dimming or turning off any lights you don’t need and use lamps or even candles where possible. Turning off all lights at night is not particularly feasible but creating ‘mood lighting’ may not only make your home feel cozy, but it may also well boost your mood the next day.
