As sunlight exposure decreases and days grow shorter, seasonal affective disorder (SAD) or seasonal depression becomes more common. As the name illustrates, those who have SAD experience the following symptoms:
- Feeling sad or having a depressed mood.
- A loss of interest or pleasure in activities once enjoyed.
- Changes in appetite; usually eating more, craving carbohydrates.
- Change in sleep; usually sleeping too much.
- Loss of energy or increased fatigue despite increased sleep hours.
- Increase in purposeless physical activity (e.g., inability to sit still, pacing, hand-wringing) or slowed movements or speech.
- Feeling worthless or guilty.
- Difficulty thinking, concentrating or making decisions.
- Thoughts of death or suicide.
Although dark days of winter have a mood lowering effect in almost everyone, it is important to recognize when this becomes a clinical diagnosis. Seasonal Affective Disorder (SAD) is a sub-type of depression with the following features:
- Recur in a seasonal pattern and goes away during other seasons
- Has been occurring during at least two consecutive winters
- Females are four times more likely to have SAD compared to males
- More common in those who have a close relative with SAD
- In Canada, anywhere from 2-6% experience SAD 
In order to be diagnosed with SAD, your symptoms must significantly interfere with your ability to function. Many people with SAD notice that their depression affects their functioning at work or school, relationships, and ability to keep up with responsibilities. Your doctor may need to run blood tests to rule out other conditions that can have similar symptoms, such as low thyroid (hypothyroidism).
What causes SAD?
The mechanism of action responsible for this condition is still not understood, but it seems to be linked to the lack of light, causing:
- Change your body’s daily circadian rhythms and sleep-wake cycle
- Change in how chemical messengers like serotonin (a brain chemical that affects mood) function.
The serotoninergic system is known to alter mood, emotion, sleep and appetite and, thus, is involved in the control of various behaviors related to physiological functions:
- Mood: Known as our “feel-good” hormone and initiates fight-or-flight, and directly impacts levels of mood, happiness, and anxiety.
- Digestion: most of our serotonin is created by enterochromaffin (EC) cells in the lining of our GI tract, playing a role in the gut-brain axis. Serotonin also impacts nausea – if we consume something that aggravates the digestive tract the gut produces serotonin to deal with the irritant through diarrhea or stimulating nausea in the brain.
- Bone mass and density: Research is mixed in this regard but it is worth noting that there is some research behind the effects of serotonin synthesis on bones. There are correlations between high levels of serotonin present in bones and an increased risk for osteoporosis.
Ways to Boost Mood In The Winter
Stay connected socially: There are currently safe and fun ways to get in your social time. Setting up weekly facetime, zoom calls or phone calls with friends and family you don’t live with is a great way to do so. You can plan activities such as doing a new recipe together or watching a new netflix show while apart, but virtually together.
Practice self care: Try to set up and maintain a daily routine complete with exercises, making healthy meals, staying hydrated and doing an activity that you find soothing and joyful. It could be a bath with your favourite book.
Light therapy/ Light box: This treatment is designed to trick your brain into thinking that the lightbox is sunlight and therefore helps prevent the onset of SAD. This consists of exposure to light daily at wavelengths that promote a regular circadian rhythm and vitamin D production. Research supports that light therapy decreases the impact of SAD and improves mood and energy levels . Bright light therapy was reported to reduce depression in one randomized controlled trial of 99 people with winter seasonal depression .
How to optimize the effect of the light box/light therapy:
- Light should be 10,000 lux 
- Full spectrum white light without UV
- Positioned at eye level or higher and 12-18 inches away
- Kept at an angle, do not stare directly at the light
- Exposure should be a minimum of 30 minutes in the early morning shortly after waking 
Keep in mind that if you are taking any medications that may make your skin sensitive to light, such as antibiotics like tetracycline or you have a family history of macular degeneration, check with your doctor before trying light therapy.
Vitamin D: Research correlates low serum Vitamin D levels with depression  and that deficiency plays a role in the onset of seasonal affective disorder . Vitamin D regulates genes which are responsible for release of some neurotransmitters. Neurotransmitters are chemicals in the brain that play a role in our mood regulation. Research on SAD suggests vitamin D deficiency is linked to a decrease in the production of serotonin.
Getting light exposure and using a light box may stimulate your own body’s ability to produce vitamin D, which will then improve mood .
A simple blood test can let you know not only if you are deficient and how much vitamin D you should be supplementing with to increase your levels to a normal range.
Magnesium: Magnesium is essential for proper brain function and mood regulation. Research indicates that without enough magnesium, you are more prone to depression. 
In one study of over 8,000 people, researchers found that those 65 years old and under with the lowest intake of magnesium had a 22 percent increased risk of developing depression. 
In a randomized controlled trial including older adults suffering from depression and type 2 diabetes, a 450-milligram magnesium supplement improved mood just as effectively as an antidepressant drug. 
Exercise: This is one of the best mood boosters our there! When you exercise you release endorphins. Physical activity is not only protective for your health but it also has been shown to improve mood and improve depression.  Studies show movement stimulates our serotonin system and increases the production of brain derived neurotropic factor. The result is an antidepressant boost in your emotional well-being as well as increased focus and performance. It can be difficult to motivate an exercise routine during this time, but shifting your perspective on what physical activity is for you is very helpful. Re-evaluate the kind of exercise you need right now and find an activity you can commit to. If you need help creating a plan, work with a personal trainer or a health care practitioner to set this up.
Nutrition: the foods we eat affect our gut-brain axis as well as encourage the production of serotonin and other balancing hormones that impact our mood and can help fend-off SAD.
- Endorphins: consume spicy foods to encourage release
- Serotonin: increase levels with foods high in the amino acid L-tryptophan and omega-fatty acids such as fish (halibut, salmon), eggs, turkey, sesame, chia, and pumpkin seeds
- General hormone release and balance: encourage this process with probiotic foods such as kimchi, sauerkraut, kombucha, miso and tempeh
Counselling: Some types of counselling, such as cognitive behaviour therapy (CBT) can be effective for SAD, particularly if it is used in conjunction with light therapy and other therapies mentioned above. CBT involves identifying negative thought patterns that contribute to symptoms and then replacing these thoughts with more positive ones.
Book today if you’re feeling the effects winter and want to help maintain balance with the seasonal fluctuations!
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