Cooler weather and the changing seasons can have a huge impact on your mental health, especially if have seasonal depression. But could cold weather cause more than just the winter blues? Let’s explore how your brain changes as the weather grows colder.
Your Brain and Cold Weather
As the weather begins to grow colder, many people experience increased sadness and decreased productivity. In the extreme, this can cause seasonal affective disorder (SAD). SAD is a type of depression which occurs only in the winter months or summer months. Winter depression usually starts in late fall as the sun sets and there’s shorter days, disrupting many people’s internal clocks and mood.
People with winter depression often experience symptoms of depression, such as:
- lower serotonin levels
- negative thoughts
- increased intake in carbohydrates
- low energy
- disrupted sleep patterns
- weight gain
- a loss of interest in hobbies
- overeating
- depressive episodes
Some symptoms can be similar to other conditions, like major depressive disorder, mood disorders, or bipolar disorder. The main difference is that SAD is usually seasonal. It often goes away with new wellness habits instead of antidepressant medications. A healthcare provider can help you create a treatment plan, which most likely will include talk therapy and lifestyle chances.
Seasonal Affective Disorder
In short, seasonal depression is a form of depression caused by seasonal pattern changes and shorter days. But the science behind this health condition might be a bit more complicated.
In 2020, researchers from the University of Ottawa were the first to examine the cold weather’s impact on indoor cognitive performance. They looked at 63,000 exams taken by adult learners. All exams were taken in an air-controlled indoor space and the only variable was the outdoor temperatures. During times of year with extremely cold weather, the test-takers saw a 10% decrease in cognitive performance.
Of course, studies before this landmark 2020 research investigated how exposure to extreme weather could impact brain health, not why.
A 2018 study looked at brain scans to determine why colder weather slows cognitive functioning. The researchers specifically looked at what happened to rat brains when exposed to extreme temperatures. When in temperatures below 5 degrees celsius, the rat’s brains produced more oxidative stress, which can cause traumatic brain injury over time.
While there hasn’t been as much clinical research around the effect of extremely cold temperatures on humans, those who are rescued from extreme cold often show signs of increased oxidative stress production too, which can lead to long-term brain trauma. This risk of brain trauma is why cold weather wilderness medicine is so important–and yet another reason not to expose yourself to extreme cold for long periods of time!
Obviously, more research could paint a better picture of cold weather’s effects on our brain. Yet, the current body of research does suggest something many of us feel. When the weather outside is frightful, we feel less productive, have decreased cognitive functioning because of a disruption in our circadian rhythm, and are more keen to hibernate (or binge Netflix) thanks to low energy levels.
Light Exposure and Winter SAD
The 2020 research from the University of Ottawa misses one main variable others point to as the reason colder seasons affect our brain: decreased light exposure. In fact, many scientists believe it might not be the cold weather that affects us, but the decreased natural light.
As the weather gets colder, the days also get shorter. When it’s dark by 5pm and not light until later in the morning, your mood may be affected. This negative effect is commonly referred to as seasonal affective disorder (SAD).
SAD affects 1 in 20 people in the northern half of the US–and does tend to be worse in colder climates. It is a variant of major depression but unlike other variants, SAD only occurs at one time of the year. There’s also a SAD seasonal to summer, but this is less common.
Characterized by depression, fatigue, hopelessness, and social withdrawal, SAD occurs most frequently in climates where certain seasons (depending on your location, worldwide) bring less sunlight.
Feel Less Sad in Winter
While the sun might appear less often, your chances of improving your mental well-being don’t have to go with it. There are plenty of treatment options, including:
- Light therapy: A small randomized, double-blind, placebo-controlled, multi-center trial from 2007 looked specifically at the efficacy of a LED light therapy device, usually a light box, in the treatment of SAD. The results found at the trial end showed the bright light therapy improved the mood of participants.
- Spend time outside when possible: if the weather permits, try to spend at least 20 minutes outside each day. A meta-review from 2019 found a positive correlation between time in nature and improved cognitive and emotional health, as well as other indicators of good mental and physical health. If you can’t spend time in nature because it’s too cold, workout or read near a window with natural light. Some studies suggest looking at nature or spending time in natural light can provide some of the same benefits as time outdoors. To super boost your time in nature, invite loved ones to get outside with you!
- Consider a Vitamin D supplement: one of the main benefits of sunlight is that it provides us with our Vitamin D. During winter, many people’s vitamin D levels drop to a dangerously low level. Low levels of vitamin D have been linked to osteoporosis, type II diabetes, psoriasis, and many other conditions.
- Talk to a therapist: seeking out a mental health professional may also help fight SAD. Cognitive behavioral therapy and psychotherapy are both ways to cope with seasonal changes and less light. Antidepressants and other psychiatry solutions are less likely to be used for SAD. If you’re curious about the best mental health solution, talk to a healthcare provider.
While the cold weather can impact our brains negatively, most of that negative impact comes from not enough time in natural light and not enough time outside. If we dress properly for the cold and understand when we need to add supplements or light therapy to our lifestyles, we can avoid many of the cognitive impacts of cold weather.
If you want even more ways to combat the cold weather before it’s in full swing, consider downloading my free guide to beat SAD. This guide provides comprehensive solutions to SAD, including supplements, activities, and more
Curious if you have SAD? Take my free SAD quiz.