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Seasonal Affective Disorder

August 31st, 2004 · Dr. Kane's Articles ·

Most of us have experienced some degree of winter blues, and as many as 10 million Americans suffer a more severe form of the seasonal depression now known as Seasonal Affective Disorder (SAD). The predominant theory as to the cause of SAD is absence of sunlight during the winter months, which causes hormonal imbalances, in particular an excess of the pineal secretion, melatonin. Although there is no definitive test for SAD, most SAD patients have high levels of melatonin in their blood. About 75% of SAD sufferers are women, which confirms a link to hormonal fluctuations. There also appears to be a genetic component, with entire families being prone to deep winter melancholia, particularly those living far enough north to experience lengthy periods of darkness for many months of the year. Artificial indoor light is not a protective or therapeutic measure to combat SAD, although high-intensity fluorescent light therapy may be curative. Light treatment has been shown to improve SAD in children also diagnosed with ADHD to the extent of allowing the kids to get off Ritalin (J Am Acad of Child & Adolescent Psychiatry , 1998; 37(2):218-220).

The pineal gland is a pine-nut sized conical gland deep in the brain behind the “third eye” which is regulated both by the action of light striking the retina of the eye and by the “master” hormonal control gland, the hypothalamus. Melatonin production increases as darkness falls, triggering sleepiness, and in some, depression. We all know, from research that began more than 30 years ago, that light is the principle remedy for SAD. John Ott wrote his illuminating book, “Health and Light”, in the 1960s while developing time-lapse photography and observing the health effects of indoor versus outdoor light on humans and animals. What is less well known is that full spectrum light is not necessary, in fact in may be harmful. UV rays are not intended to reach the retina; green light is the important wavelength for the retinal-pineal axis, and I have personally helped many people overcome depression by bathing regularly, ideally nude, in green light. (“Treatment of seasonal affective disorder with green light and red light” Am J Psychiatry 1991 Apr; 148(4):509-11) Moreover, light need not shine into the eyes at all to relieve SAD. Light shining on the backs of people’s knees effectively advanced their internal clocks so they woke closer to daybreak, triggered by altered timing of melatonin release, according to findings published in the journal Science (Science 1998; 279:333-334, 396-398). Other important considerations for light therapy are timing and intensity. The idea is to push out the edges of the day, particularly in the morning, so first morning light treatment is by far the most effective. Ideally, upon waking, you would place yourself within 10 feet of a 10,000 Lux bulb (or series of bulbs totaling 10,000 LUX) and stretch, meditate or read for 20 minutes. One group of investigators found that the most beneficial time to take light therapy was about 3 hours after the midpoint of sleep. (Archives of General Psychiatry; Jan 15, 2001; 58; 69-75) This is not practical for most, however, so light therapy upon arising is a good second best for relieving winter depression. Most folks appreciate benefits within a few days, but you need to be consistent with the treatment. Rarely, anxiety or headaches may result from bright light therapy, in which case start with half the time and twice the distance from the light, and work up to the full dose. (Read The Section Getting Set Up for Light Therapy below for more information on putting together your own lightbox.)

Patients with SAD who had responded to a standard regimen of daily 10,000-lux therapy were given a tryptophan-free amino acid beverage, which reversed the benefit of the light therapy (Arch Gen Psychiatry. 1998;55:524-530). What this means is that tryptophan, 5HTP and serotonin (all biochemically related) play an important role in how the light therapy works. Tryptophan, a precursor to serotonin, has proved a potent anti-depressant agent, which unfortunately fell out of favor in the early 1990s due to one contaminated batch reaching the market. Some alternative healthcare providers believe that tryptophan has been unjustly vilified in order to enhance sales of the much more expensive selective serotonin re-uptake inhibitors (SSRIs, such as Prozac). Tryptophan is a weakly binding amino acid, which means that a high-protein meal tends to cause tryptophan excretion, whereas a carbohydrate meal encourages tryptophan absorption. (Check out an interesting book on this topic: Potatoes, Not Prozac by Kathleen DesMaisons.) Besides using prescription SSRIs, you can encourage tryptophan uptake with dietary manipulation, such as getting a complex carbohydrate meal at least once daily. Most of us, with or without SAD, have noticed increased carbohydrate craving in the winter; likely because our melatonin levels are higher and serotonin levels lower. Refined sugar snacks will not do the trick; in fact sugar will make depression worse. But vegetable starches such as carrots, potatoes, bananas, dates and figs will all raise tryptophan, and therefore serotonin, levels in the body for several hours after ingestion. If you prefer to use tryptophan, its precursor 5-HTP, 50-200 mg at bedtime can effectively combat both depression and insomnia.

Despite touting the value of UV-free light for SAD, UV does confer the benefit of stimulating Vitamin D formation in the skin. And Vitamin D deficiency is linked to various health problems including bone disorders, several hormonal cancers, impaired immune response, hypertension, multiple sclerosis and mood disorders, including SAD. Good food sources include eggs, lever and fish, or lots of fortified milk, but many of these food choices are difficult to find in organic form. My favorite Vitamin D supplement (besides sunshine) is Cod Liver oil; 1 tsp. in the winter will provide about 600 IUs daily. Do not take Cod Liver oil in the first trimester of pregnancy because of high Vitamin A levels.

Anyone with small children has likely recognized the benefit of tepid (not too cool, but not warm) water in cheering a moody youngster. Remember this very simple, readily available, hydrotherapy technique: a coolish bath in the morning will do wonders when you want to have a good day.

Spend time outside, even if the sunlight is muted, especially if you can get well away from buildings and receive light in a 360 degree radius. Twenty minutes outside daily is a minimal requirement for well-being, preferably while moving vigorously.

The roots of the word melancholy mean “black bile” in Greek. To keep your liver (the organ that secretes bile) functioning well, minimize or avoid alcohol or exposure to other solvents. Eat plenty of beets. Artichokes and the other famous liver-cleansing thistle, Silybum marianum (Milk Thistle) are also very beneficial. Make sure your Milk Thistle is standardized and contains about 250 mg of silymarin (the active ingredient) per dose.

The plant kingdom has much to offer us not only as vessels of distilled sunlight but as central nervous system nutrients. Plant nervines are widely available in health food stores and can be matched to your particular presentation by a skilled herbalist or naturopathic doctor. You can start by reading up on Lavender (works by smell), Chamomile (great for kids), Verbena (good for depression with stomach upset), Valerian (can be effective for pain and depression), Melissa (helps with digestion, anti-viral), and Scutellaria (helpful for depression with constipation, or headaches).

And lastly, a good quality, high potency, multi-B vitamin complex is critical for beginning to correct depression triggered by stress. For many, the low levels of light in the winter are profoundly stressful.

Getting Set Up for Light Therapy

  • You don’t need “full spectrum” lighting in fact the UV may be harmful to your skin and eyes. Choose “broad spectrum” lights instead, which omit the UV and feature the healing green wavelength.
  • The intensity of the light is what counts: go for 10,000 Lux either from a light box or install four 2,500 Lux bulbs in existing fixtures in the room where you’ll spend early morning time.
  • Choose fluorescent bulbs, which diffuse the light safely, rather than incandescent bulbs, where the light comes from a small source, like a filament.
  • You can use compact fluorescent bulbs that screw into a normal light socket. These retail for about $50 per bulb; however, they use 80% less electricity than a typical bulb and last 10,000 hours, which is about ten years.
  • Bulbs or your portable light box need to be 2 to 5 feet away from your skin, which means ceiling lights will not be as effective.
  • A nice way to use your lightbox is to plug it into an electric timer and orient it towards your bed.

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