SAD is a mild form of depression that presents itself primarily in the winter months as anxiety, decreased activity, irritability, and more sleeping than usual. People with SAD often isolate themselves and withdraw from social situations. They may find it difficult to concentrate and find it difficult to enjoy anything. As opposed to most depressive conditions, SAD is actually characterized by an increased appetite. Weight gain and carbohydrate cravings, especially sweets, are also typical symptoms of SAD.
SAD is associated not only with low levels of sunshine but also low levels of the sunshine vitamin—vitamin D. Sunlight is converted to vitamin D when it hits unprotected skin. Some SAD patients use full spectrum light therapy to improve their moods. This therapy exposes them to a light of certain wavelengths that helps the skin produce some vitamin D.
More research on the link between Vitamin D and its exact role in depression is needed. Thankfully, the amount of research in this area is currently growing. One theory suggests that Vitamin D aids in the production of certain brain chemicals called monoamines. Anti-depressants work much the same way—increasing the levels of monoamines in the brain. It is thought that vitamin D increases the monoamine serotonin, a hormone that contributes to feelings of happiness.
In one study conducted on SAD patients, about half of the subjects received Vitamin D in supplement form. The other half only received light therapy. Although both groups improved their vitamin D status, the group that received Vitamin D in supplement form showed improvements in their depression while those who only received light therapy showed no significant changes.
Some foods often fortified with vitamin D include fortified soy milk, low-fat milk, orange juice, yogurts, cereals, and breads. Foods that naturally contain vitamin D include oily fish such as salmon, herring, canned sardines, and tuna. Eggs and shitake mushrooms are other natural sources of Vitamin D. As you can see, winter can really put someone in a compromising situation. With limited exposure to sunlight and limited sources of naturally-occurring vitamin D in foods, many are prone to a low Vitamin D status. A Vitamin D supplement may be needed to get an adequate amount.
If you're (not) happy and you know it...
Serotonin, the "happy" hormone, is low in those dealing with SAD. A deficiency in this hormone can also cause constant cravings for carbohydrates. A balanced, healthy diet will guarantee you are getting enough tryptophan, an essential amino acid that serotonin is made from.
Folate and vitamin B12 also have a role in serotonin production. Folate prevents excess homocysteine levels, a chemical in the blood that can block the production of serotonin and blood supply to the brain. There are many colorful foods rich in folate and vitamin B12 that can help fight away the winter blues and that are simple to include as part of a healthy, balanced diet. Some examples are whole grains, lentils, oats, beets, spinach or other leafy greens, oranges or other citrus fruits, rhubarb, avocado, garbanzo or other dried beans, peas and green beans, strawberries, low-fat dairy, mackerel, fresh tuna, and wild salmon.
Limited but promising evidence shows that magnesium deficiency can be a cause of depression. One study noted that all patients that were significantly depressed were also deficient in magnesium. Although we await further study, it is important to prevent a deficiency in this mineral. Magnesium is found in small amounts in a wide variety of foods, such as legumes, nuts, seeds, dark green vegetables, and milk. Since our soil tends to be deficient in many nutrients, a high-quality multivitamin will ensure you get all the micronutrients and minerals your body needs.
Two Birds. One Stone.
Exercise helps. Exercise under the sun helps even more. Staying active outside will help you prevent weight gain and feel more energized throughout the day while you also get a supply of vitamin D. Take a walk during lunch hours, when the sun is brightest. If available in your area, try out a winter sport, such as ice skating, snowshoeing, or skiing. Raking leaves and shoveling snow are more than a chore! They are a great way to pack more physical activity into your day.
Boost Your Mood!
Many resort to simple, sugary carbohydrates to improve their mood. This happens because the happy hormone, serotonin, is released during carbohydrate intake. In reality, they are digging themselves a deeper hole. This "sugar rush" leads to a "sugar crash"—a low energy state due to an imbalance in blood sugar. This "low" physical feeling can contribute to a "low" mental feeling that aggravates the depression with feelings of fatigue, irritability, and headaches.
It is important to keep your blood sugar stable. Stay away from super sweet, simple, and processed carbohydrates. Complex carbohydrates help keep your blood sugar steady and come packed with fiber. Keep healthy carbohydrates handy in case a trip to the grocery store may be difficult to do. Oatmeal, whole grains, lentils, pre-washed and colorful veggies, fruits, or brown rice are great examples. EnergyFirst protein shakes are the perfect meal, post-workout, or snacks to keep your blood sugar stable. They are especially helpful when you don't have the energy to cook a full meal.
Diet and exercise aside, take some practical steps to make your surroundings SAD-proof. Try not to confine yourself to windowless spaces or basements for too long. Stay connected with your friends and family—your social circle is your social support. Come spring, you can watch the snow (and SAD) melt away.
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WebMD. Understanding seasonal affective disorder basics. Available at http://www.webmd.com/depression/understanding_seasonal_affective_disorder_basics. Accessed October 15, 2013.
Miller AL. The methylation, neurotransmitter, and antioxidant connections between folate and depression. Altern Med Rev. 2008:13(3):216-226.
Cox RH, Shealy N, Cady RK, Veehoff D, Awell MB, Houston R. Significant magnesium deficiency in depression. Available at: http://www.oasisadvancedwellness.com/learning/magnesium-deficiency-depression.html