Short days, limited sunlight, and cool wet weather can make many of us feel “blue” at times. The concern is when your gloomy mood follows a seasonal pattern and impacts your ability to function normally. This is a sign that you may be experiencing a form of clinical depression called seasonal affective disorder (SAD). According to the Canadian Mental Health Association, 2–3% of Canadians are diagnosed with SAD at some point in their lifetime, and 10% of depression cases are caused by SAD.
Although some people can experience SAD in the spring and summer, it is most commonly brought on during the autumn and winter seasons. While the exact cause of SAD is not confirmed, it is known to be hereditary and some experts believe it is triggered by a lack of sunlight during the winter. 
If you are experiencing symptoms of SAD, it is important to consider your diet and whether it provides all of the nutrients you need for healthy brain function, especially the following:
Vitamin D is known as the “sunshine vitamin” because the body synthesizes it when the skin is exposed to sunlight. When your exposure to sunlight is low, your body relies more on dietary sources.
Vitamin D plays a key role in brain function. Its receptors are widespread throughout brain tissue, and are specifically designed for receiving chemical signals from vitamin D. Despite its importance, 4% of Canadians ages 6–79 are deficient in vitamin D, believed to be caused by a low dietary intake and limited sunlight exposure. 
It can be challenging to maintain adequate vitamin D levels through diet alone because few foods contain naturally occurring vitamin D. Those that do include:
- cod liver oil
- organ meats
- egg yolk
- oily fish
This is why supplementation is one of the most effective ways to maintain a healthy vitamin D intake throughout the year. Vitamin D3 1000 IU is an easy-to-take liquid formula that helps prevent vitamin D deficiency. It contains 1000 IU of vitamin D3 per drop in a base of MCT oil from coconut and RSPO-certified palm kernel for enhanced absorption.
Folate and vitamin B12
When you’re under stress, there is added pressure on the bodily systems that rely on vitamin B12 and folic acid. You may need to consume more of these vitamins to maintain your health during times of heavy mental and physical demands. 
Studies show a link between depression and low blood levels of folate and vitamin B12, which may stem from its role in metabolizing the amino acid homocysteine. You can rev-up your intake with folate-rich foods, including:
- fortified whole-grain cereals
For a good dose of vitamin B12, focus on eating:
- dairy products
Supplementation is also an effective way to increase vitamin B12 levels. B12 Methylcobalamin is the biologically active form of vitamin B12, and the form most readily absorbed into the body. The sublingual tablets are a convenient format for anyone who has difficulty swallowing pills.
Omega-3 fatty acids
Omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are important fats that the body needs for healthy brain function.  They are an essential part of the diet because the body cannot make them on its own. They are also key building blocks of brain cells and are used to fuel brain metabolism.
DHA is an especially critical fatty acid because of its structural role in the cerebral cortex and communication centre of the brain. While everyone benefits from eating omega-3 rich foods, they are particularly important for people who want to sharpen brain function and mental health. Great sources include:
- marine algae
- flax and chia seeds
- soy products
- cold water fish such as sardines, mackerel, and salmon
For people who have difficulty meeting their essential fatty acid needs, SeaRich Omega-3 is a great-tasting formula made using the freshest, highest-quality fish oil. Each teaspoon provides 750 mg of EPA and 500 mg of DHA in triglyceride form for better absorption and no fishy repeat or odour.
Your recovery strategy
There are many approaches and support systems available for relieving sysmptoms of SAD. Whether you are experiencing a light case of the winter blues or a severe onset of SAD, nutrition should always be a part of your recovery strategy. Be sure to consult your health care provider regarding medical questions or concerns about your health. You can also contact the following professional organizations for more information about mental health:
- Canadian Mental Health Association
- HealthLink BC
- Mood Disorders Association of BC
- Mood Disorders Association of Ontario
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