Combating Seasonal Affective Disorder (SAD)

Katherine Chavez, ND


Fall and Winter bring with them less sunlight-and thus a shift in circadian rhythms. Early morning sunlight no longer hits the retina, the nerve-rich back of the eye, shutting off production of melatonin. Increased production of melatonin decreases supplies of its precursor serotonin. This results in many of the symptoms of Seasonal Affective Disorder (SAD): depression, anxiety, irritability, fatigue, hypersomnia, reduced libido, increased appetite, carbohydrate cravings, and weight gain. Less sunlight hitting our skin also means less production of vitamin D-associated with depression, fatigue, and weight gain.


SAD affects between 15 and 25 percent of the population. People at highest risk of developing the condition include:

· women

· young adults ages 20 to 30

· people with a history of depression or bipolar depression

· those living at higher latitudes

· people with darker skin pigmentation.


There are many techniques to prevent or improve the symptoms of SAD. Increasing serotonin levels is a great place to start. On sunny days, get outside. This will stop the production of melatonin, which will increase serotonin reserves. On cloudy days, light box therapy is a great replacement. Studies show that exposure to 10,000 Lux of light 1 to 3 ft. away directed at your eyes for 30 minutes each morning is 70 percent effective, with people reporting positive effects in two to three days. This is more effective then serotonin reuptake inhibitor drugs in some studies. Reputable companies Verilux and Alaskan Northern Lights sell light boxes.


In addition to increasing serotonin levels, sunlight also is key to vitamin D. However, many foods contain vitamin D, too. The best sources are cold water fish such as sardines, salmon, and tuna. Shrimp, mushrooms, and sunflower seeds also contain vitamin D. Many foods, like dairy products, are fortified with vitamin D. For most people, however, vitamin D supplementation is often necessary. (Note: Vitamin D is a fat soluble vitamin, which means you can get too much. Testing prior to starting the supplement is important.) Exercise also increases serotonin, as well as blood flow to all tissues. This raises energy levels, sensitizes thyroid receptors to thyroid hormone increasing metabolism, and releases endorphins that improve mood and libido.


Other neurotransmitter imbalances may also contribute to SAD. This is likely why people with a history of depression are more vulnerable to SAD and would be good candidates for neurotransmitter testing. The at-home urine test reports levels of serotonin, GABA, glutamate, PEA, dopamine, norepinephrine, and epinephrine. Correcting any neurotransmitter imbalances with amino acids, B vitamins, and herbs can greatly reduce depression and anxiety throughout the year.


Aromatherapy is a safe and enjoyable way to reduce anxiety and depression. The olfactory tract transmits smells directly to the limbic system in the brain.


This part of the brain (including hippocampus, amygdala, hypothalamus) is involved with emotional behavior and memory. This is why many studies show smells can relieve depression and anxiety. To reduce depression, lavender, bergamot, and jasmine are the best studied. To reduce anxiety, lavender, rose, orange, bergamot, lemon, sandalwood, clary sage, Roman chamomile, hiba, and geranium are the best studied. These oils can be used topically on your skin, in diffusers, or on your clothing. The only side effects: that you will smell lovely.


Talk therapy, and biofeedback are other excellent ways of reducing anxiety and depression. These techniques can help to recognize and change thought patterns and neurological pathways that may be contributing to SAD symptoms.



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