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Seasonal Affective Disorder (SAD) is a common occurrence during the darker winter months. As many as 20 percent of people may experience some degree of low mood in the winter, with 2-10 percent of people experiencing significant depression.



Symptoms of SAD include:

– Lack of energy

– Difficulty concentrating or completing tasks

– Feelings of hopelessness

– Lack of pleasure

– Loss of sex drive

– Abnormal sleep and eating patterns (can be either too much or too little)

– Food cravings centered on carbohydrates

SAD sleep issues usually lean toward oversleeping and difficulty getting up in the morning.  While the cause of SAD is not completely understood, there are several trends that have been observed.

SAD is less common in:

– Places with more sunlight – SAD tends to be rare in equatorial/tropical climates (example:  SAD rate is 1.4 % in Florida), and is more common in far northern climates (example:  SAD rate is 9.9% in Alaska, and is common in Canada, Ireland & much of Scandinavia)

– Populations that eat a lot of fish – SAD rates are lower in Iceland and Japan than in other far northern countries. These two nations consume roughly three times more fish than folks in other northern areas.

Sunlight affects two hormones very directly:  Melatonin and Vitamin D.

Melatonin is a hormone involved in sleep regulation and is a key part of our circadian rhythm. Because of this it affects other hormones as well. Melatonin is suppressed by bright light and is released in the dark. Varying amounts of melatonin release were biologically a big part of how our bodies tracked the seasons and phases of the moon before we had artificial light, alarm clocks and smart phones. Melatonin is closely related to serotonin, which has major impact on mood and has the potential to affect sex drive and the menstrual/ovulation cycle. Too much melatonin tends to slow us down. Not enough melatonin often means we don’t get enough rest.

Vitamin D is an essential vitamin and can also be considered a steroid (anti-inflammatory) and a hormone. Some of the best known impacts of Vitamin D in the body are on mood, energy and bone strength. Vitamin D is produced in the body in response to sun exposure, but Vitamin D can’t be activated by the sun if its precursor, cholesterol, is not present. Cholesterol is converted to “pre-vitamin D” in the skin by sun exposure. This “pre-D” is then converted by the liver and finally the kidney into the final active form of vitamin D. Low fat, low cholesterol diets and cholesterol-lowering drugs can all contribute to low vitamin D levels. However, foods that are high in vitamin D (such as salmon, eggs, cheese and grass-fed beef) are also high in cholesterol, so eating these foods can help support your mood.

Recommendations for avoiding SAD this holiday season:

Get your vitamin D levels tested. If your levels are below 80, talk to your practitioner about supplementing with a robust dose of vitamin D3.

Bright light in the morning (7:30 am) is very important to suppressing daytime melatonin expression and keeping the circadian rhythm on target. Some people may benefit from small night time doses of melatonin as well, but this may backfire in the absence of bright light first thing in the morning.

Exercise is vital to maintaining general health, and also positive mood. Exercise is as effective as anti-depressants for mild to moderate depression. It releases endorphins and serotonin (our natural feel-good chemicals). Combined with fresh air and sunshine, exercise can be pivotal in the prevention and treatment of SAD. One of the simplest things to do is to go for a brisk walk outside first thing in the morning before you start your day. Even 10 minutes often makes a big difference.

Take Cod Liver Oil, which is high in Omega 3’s, cholesterol and vitamin D. Ingest 1-3 teaspoons per day to support healthy brain function, heart health and mood.

Be thoughtful about holiday foods. Holiday foods are much higher in carbohydrates and sugars, dairy and gluten. For many people gluten, dairy and refined carbohydrates cause significant inflammation in the gut as well as the brain. Keeping your diet healthy does not mean that you don’t get to enjoy delicious holiday feasts, but look for more healthy, whole-food versions of those cookies and pies. Don’t forget that there are many delicious fall and winter recipes for fruits and vegetables, and gluten-free and paleo options for treats.

Stay connected.  Spend time with people whose company you truly enjoy.  Share a meal, take a walk outside, laugh, and remind each other to take your vitamin D!

by Becky Andrews ND*, MSA, LMT

Dr. Andrews* sees patients at Peoples Wellness Center Central in Austin, TX.

*Naturopathic doctors are not currently licensed in the state of Texas.