Why Mood is Affected by Less Sunlight & What to do About it

Even though spring is on the way, we are still dealing with our shorter, darker winter days. More darkness. Less sunlight. 

Although I don’t mind winter, the turning inward, the quiet, the darkness, around this time every year my body and mood start responding to the long winter. Even if my introvert self likes the season, my body is ready for the sun. Ready to be outside again. Ready for longer, brighter days.

Here’s the deal…sunlight stimulates cells in your eye that connect to your brain. The part of your brain it affects is known as the “master clock.” This master clock coordinates the biological rhythms in our bodies. This includes sleep-wake cycles, hormone release, neurotransmitter production, digestion, body temperature, and a host of other important bodily functions.

Things can really get thrown off in the winter when we have less sun.

For instance, at this time of year we produce less serotonin—one of our brain chemicals that affects mood and energy levels. Also when there is less light, we produce more melatonin, and this can make you feel groggy and fatigued, even as early as 4:00 PM in the winter! If that wasn’t bad enough, you are also getting less vitamin D as this comes from sun exposure. Low vitamin D for some people can cause feelings of depression. Fortunately, you can help yourself escape the darkness. 

All you have to do is expose yourself to light.

There are a variety of commercially available light boxes. The two main ones are full spectrum (white) and blue light boxes.

Blue light boxes emit only blue light and have the potential to help in balancing brain circuits, alleviating depression, and increasing alertness. Full spectrum light boxes imitate natural sunlight and emit blue light along with all the other colors on the electromagnetic spectrum.

At this time. although research on blue light boxes has shown that they may be even more effective at treating seasonal depression than full spectrum light boxes, full-spectrum light boxes are considered the standard of care in treating Seasonal Affective Disorder (SAD) as they are backed by more research than the blue lights. In practice I’ve seen the blue lights be more effective but it probably varies person to person (like everything else!) 

Please note that although they are generally safe, these boxes are not entirely without risk. The full spectrum light boxes are meant to eliminate or greatly reduce the presence of ultraviolet rays but they still may be present and carry some risk of harm. The blue light boxes, even if you don’t look directly into them, can cause eye issues for some people. You should discuss these boxes with your doctor to see what is right for you. 

What is important to note is that, as humans, we have evolved in the presence of natural sunlight.

Even with the use of a light box, it is important to “put your face in nature,” often.

Natural sunlight contains red light which helps relieve inflammation; near-infrared which increases melatonin production and helps with sleep. Natural sunlight also contains UVB which is required for vitamin D production, as well as a whole host of other wavelengths with many other biological effects.

What this means is that exposing yourself to natural sunlight is vital, and that means going outside, even if it is raining or snowing! Although we are not getting as much light as we would in summer months, going outside in on a winter day still exposes us to full spectrum light and its associated benefits. Plus, walking in nature has its own scientifically proven benefits including decreased anxiety and less rumination (obsessing.) When you move your body you also increases production of mood-improving hormones like serotonin. And finally, from a Chinese medicine perspective, moving your body moves your qi, or energy—also helping with feelings of depression or being ‘stuck.’ I feel like walking outside is the ultimate ‘twofer’ for mood and energy. 

That said, it is still important to supplement with oral vitamin D as UVB (ultraviolet) rays are required for us to produce vitamin D. In winter, it is improbable, if not impossible, for most people to get enough exposure to sunlight to create enough vitamin D naturally. You can read more about supplementing vitamin D here

So, get out in the rain and walk! And before you do that, throw on your light box for 20-30 minutes right after you wake up in the morning! These strategies are sure to help you in fighting off seasonal depression this winter.

Yours in Health,

Why Mood is Affected by Less Sunlight & What to do About it | Dr. Samanthta

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