Lighting the Way to Wellness
By Joel Fuhrman, M.D.www.drfuhrman.com
Therapeutic Light Is An Effective Treatment For Depression
Light therapy is no longer considered a therapy only for seasonal affective disorder (winter blues). It has been found to be effective for all types of depression, including major depressive disorder and bipolar depression. In 2005, a metanalysis (combining results of multiple independent studies) of bright light therapy for depression found that “bright light treatments are efficacious, with effects equivalent to those in most antidepressant pharmacotherapy trials.1 The evidence is so compelling that I believe that every primary care physician and psychiatrist should be well versed with the use of this treatment modality.
Bright light therapy for seasonal affective disorder (SAD) has been utilized and shown to be effective for more than 20 years. In recent years, this therapy has been shown to be effective for major depressive disorder (MDD), premenstrual and postpartum depression, attention deficit disorder (ADD), bulimia nervosa, premenstrual syndrome (PMS), sleep disorders, insomnia, and more.
Studies done during the last five years that are of particular interest are the investigations into the most effective exposure schedule, duration, intensity,wavelength spectrum, and timing of the treatment. For example, years ago researchers used 2,500 lux lighting for three hours in the morning and evening. Although this was effective (and there certainly can be multiple effective treatment schedules), recent studies reveal that increasing light intensity to 10,000 lux in 30-40 minute sessions gave higher remission rates.
Benefits Of Morning Light
Morning light has been shown to be vastly superior to light exposure later in the day. In fact, light therapy given 7.5-9.5 hours after melatonin onset yielded twice the remission rate (80% versus 38%) of light given 9.5-11 hours after. 2 Melatonin onset usually occurs about 10:00 pm, but can vary. Therefore, to maximize the likelihood of a treatment response, the light treatment should be given as close to dawn as possible.
Sessions should begin within 10 minutes of scheduled wake-up times, and those using light therapy for depression should wake up relatively early to begin treatment first thing in the morning. Since light therapy is most effective when given between 6:00 and 7:00 in the morning, light treatment should begin before sunrise in the winter. Depressed patients who sleep later than this need to be woken up and have their bedtimes adjusted to synchronize with the “forced” morning wakening. They need to readjust their circadian rhythms and, in many cases, shorten their sleep duration. Oversleeping must be discouraged. Sedating medications that lead to late morning wakening are counterproductive to the effective potential of light therapy.
The timing of the therapy is important; evening light therapy can be counterproductive, and if scheduled too late, can result in insomnia and hyper-activation. If morning light is timed too early, one could develop premature wakening. The effectiveness of this therapy is extremely dependent on strict compliance with the schedule, and morning treatments should not be skipped. Patients sometimes ignore the alarm or attempt to test whether improvements can be obtained without strict adherence to the protocol, which can interfere with the high expected response rate. The behavioral investment in this mode of care exceeds that of simply popping a drug into your mouth once per day.
Hypersomnia patients (over-sleepers) who are unable to awaken when instructed can begin light therapy at the time of habitual wakening, and then can be shifted gradually to an earlier time. The light therapy will usually help with the adjustment to an earlier wakening and will lessen the need for so much sleep. There is evidence that oversleeping can produce brain biochemistry more susceptible to depression,3 so using the light to lessen over-sleeping can be helpful.
For those with recurrent mood disorder histories, proper exposure to light should be an important part of their health program. Once remission is obtained, light therapy should be continued until the climate and time of year enables replacement with natural light outdoors in sunshine. As the season warms, replace the light treatments with walking or working outdoors facing in the direction of the sun for 30 minutes each morning. During overcast and rainy periods of time, and before mid-fall and mid-spring, the light therapy should resume again.
Beneficial Mechanisms Of Action
There are multiple mechanisms of action of enhanced lighting. First, there is a direct energizing component by light exposure, no matter what the time of day. Neurologically, this is called “autonomic activation,” where direct exposure to light serves as an immediate performance enhancer. Second, there is an indirect component that regulates the internal body clock, depending on the time of day of the light exposure.
Without adequate light exposure, the human biological clock is at risk of slipping later and later into the 24-hour daily cycle, moving our bodies into a different time zone with a mismatch to our work and sleep schedules. This slippage results in daytime fatigue, difficulty in awakening, and mental “fogginess,” often accompanied by mood slumps, and a switch in appetite to “comfort” foods, as well as problems falling and staying asleep at night that are uncorrectable by sleeping pills.
Neurochemically, the drifting circadian cycle results in delayed nighttime production of the hormone melatonin by the pineal gland. Melatonin production is normally high throughout the night while we sleep, but delay of the circadian clock can result in an overshoot of melatonin production into daytime working hours, which can lead to depression.
Normal adults need about six to eight hours of sleep each night. When some depressed individuals sleep excessively, it makes it harder for them to recover from their depression. Besides melatonin, there are other depression-triggering substances that become overproduced with too much sleep. Exposure to bright daylight and high levels of illumination mimicking the sun coming off the water on the beach suppresses the sleep hormone melatonin and other depressogenic substances, and also stabilizes the forward slippage of the body clock.
Increased light levels are thought to enhance the production and utilization of the body’s natural neurotransmitters— including serotonin, dopamine, and norepinephrine— substances that are identified with improved daytime alertness, better mood and stress relief, improved motor skills, and productivity. When our natural body clocks are destabilized by dim indoor lighting and lack of sunshine, restless sleep, insomnia, daytime sleepiness, irritability, and depression are more likely to occur.
Melatonin is manufactured from serotonin. When melatonin levels increase (from inadequate morning light exposure), serotonin levels decrease, since more serotonin is converted to melatonin. Exposure to light lowers melatonin levels and increases serotonin levels.
Whether you have a mood disorder or not, enhanced light exposure in the workplace and home is important for improved alertness, energy, and mood, and serves as a countermeasure to deficient indoor lighting conditions. Indoors, we live and work continuously under what is usually only a twilight level of illumination, even though the lighting seems visually adequate. Out-of-doors, diminished seasonal light availability, due both to winter’s delayed sunrise and early sunset as well as increased inclement weather, has a pervasive depressing influence for at least half the population.
Light Therapy For Insomnia
Often, shortening the hours lying in bed trying to sleep can help with insomnia. Are you lying in bed at night unable to fall asleep or stay asleep? Most people who experience insomnia turn to drugs. More and more drugs seem to be the recommended answer to everything today. But a much safer approach than becoming dependent on drugs is light therapy, accompanied by weight training. The combination of early morning light and exercise helps normalize melatonin and growth hormone secretion. By itself, exercise should not be expected to have a major therapeutic effect to defeat depression or insomnia, but in conjunction with other positive interventions, it can be an important part of the entire healing process.
If you have trouble falling asleep at night or wake in the middle of the night and lie there for hours without sleeping, try to consolidate your so that you sleep better, get quality sleep, and spend less time in bed. For example, go to bed a little later and wake up at sunrise. Use high intensity light or, if you live in a warm sunny climate, get outdoors in the sun early in the morning before breakfast. Get your internal sleep clock adjusted to the natural light cycle. Don’t sleep later than 7:00 am in the morning, and get outside into the sunshine. If you have trouble falling asleep (even if you do not fall asleep until three in the morning), consistently wake yourself at dawn with either natural light or with a high intensity electric light.
After three to five days, you should find that you are able to fall asleep without lying in bed half the night. Develop a schedule that works for you. Here is a suggestion to start with. Start out going to bed at 1:00 am and waking yourself at 7:00am. Don’t attempt to go to sleep until 1:00am, but get up with an alarm clock at 7:00am, no matter what time you actually were able to get to sleep. Don’t nap. Wait until 1:00 am again before going to bed. It is better to sleep soundly for five or six hours than to lie in bed all night unable to sleep. If you can’t fall asleep for a long time at 1:00 am, the next night put yourself to bed at 1:30 or 2:00 am. Wake up on time with the light. Eventually, the combination of the morning light and shorter time in bed should help you get rid of your insomnia without drugs. If you find you are becoming too tired with only five to six hours of sleep, start going to bed a little earlier, shifting bedtime gradually back by 15-30 minutes until you have customized the regimen to your needs. Eventually, you will find the proper bedtime to match your dawn wake-up time.
Recent studies testing the wavelength and spectrum of light found that the design of the bulb lamp and screen are important for safe and effective therapy. Lamps are sold that provide excessive visual glare and naked bulbs that may harm the eyes. Intense illumination below the eye level, or augmented UV radiation, also should be avoided.
Broad spectrum, white illumination has been shown to be the safest and most effective. In comparison, ocular exposure to high infrared illumination, which comprises 90% of the output from typical incandescent lamps, poses a risk to the eye. These types of incandescent lamps, in spite of being marketed for bright light therapy, should be avoided.
We researched to find the best features and cost and then purchased a light that was designed to meet the specifications of the researchers at Mt. Sinai Hospital. Now available in our office and from DrFuhrman.com, the Therapeutic Light incorporates the features that have been demonstrated in the medical literature to be critically important for the effectiveness of light therapy for depression, ADHD, PMS, fibromyalgia, and sleep disturbances. It is the finest clinical light system available at a reasonable price ($159.99).This light has been used in research trials and contains all of the critical features recommended in therapeutic light in the recent Mt Sinai Hospital study.
Of note is that a downward tilting fluorescent protected by a smooth diffusion screen curved at the proper angle and set at the right height above a desk surface is important. Research has to be integrated into the design of the light, which is important, especially if it is going to be used for therapeutic purposes. I recommend positioning the light 12 to 18 inches in front of you on the desk. The center of the light will be above the level of your eyes, and you can read or work beneath it while the light enters your eyes indirectly from above. This distance and height will minimize eye strain, but if any nausea or headaches or other symptoms develop, sit further back from the light and inch in a little closer with time.
There have been some reports of hypomania occurring early in treatment in bipolar patients (cycling manic-depressives). In these cases, light therapy has been shown to be better used later in the day. Therapy also can be started at a further distance and then brought in to the therapeutic range gradually.
Photosensitizing medications are also contraindicated with light therapy. The photosensitizing drugs of most concern include, but are not limited to: imipramine, phenothiazine, lithium, chloroquine, hydrochlorothiazide, porphyrins, psoralens, and tetracycline. Melatonin and hypericum supplements are also contra-indicated. Care should be taken when on medication, and the light therapy should be used only with consultation with a physician because lessening of drug dosages may be important to preventing overtreatment and increasing the medication’s side effects. Patients with eye diseases, especially retinopathy, should not use this therapy.
Negative Ion Generation Enhances Protocol
One way to treat depression is to move to the Caribbean and walk on the beach in the early morning sun, soaking in the light and the negative ions coming off the water. However, most of us can’t live on a warm beach most of the year.
Negative air ionization is a new modality for depression. Our senses are not able to detect the presence of these negative ions in the air, but they do something beneficial to the brain. Negative ions are high in the natural forest and at the seashore, and they are low in urban environments and heated and air-conditioned interiors.
As an example, in healthful outdoor environments such as mountains and country meadows, the negative ion concentration is typically 2000 to 4000 negative ions per cubic centimeter. In extremely healthful and invigorating environments, such as near a large waterfall, the negative ion level is around 1,000,000 per cubic cm. By contrast, the negative ion concentration in an indoor work environment is between 100 and 200 negative ions per cubic cm.
The antidepressant effect of a high concentration of negative air ions has been demonstrated in patients with chronic depression in a few different studies. The most recent study used a strong ion generator exposing participants with major depression to a high flow rate of negative air ions for one hour each day, and it demonstrated a 50% rate of remission for depressed patients.4 There are lots of electric air purifiers that generate negative ions, but they usually do not generate the high levels of negative ions needed therapeutically for mood disorders. We have researched the best options for efficacy and cost for our patients and we have what we feel is the best choice available at drfuhrman.com.
The goal is to combine light therapy, nutritional therapy, and ion therapy to achieve high rates of remission that should exceed the response rate to medication, without the side effects. Mimicking a more natural light and ion exposure that would be found in a warm sunny beach climate can help with migraines, attention difficulties, restless legs, fatigue, and anxiety.
Of course, not all emotional and mental problems are biochemically induced. For example, dysfunctional childhoods and genetic factors each can play a role. Counseling, personal growth, change in life situations, and insight are complementary adjuncts to therapies to improve brain chemistry. Nevertheless,there is a clear biochemical predisposition to depression in our northern, limited sunlight, polluted environment where minor stresses in life are able to grow into major depressive disorders.
Therapeutic Light Dr. Fuhrman’s Therapeutic Light Has These Beneficial Features:
- 10,000 lux setting for therapy
- A second lower (2500 lux) intensity adjustment for general use
- Flicker-free light source diffused with OP-3 UV filtration
- Broad field of vision to minimize glare—the greater the size, the less glare
- Gently curved polyethylene diffusion to assure proper angle entering eyes
- 6500 Kelvin CIE daylight standard—averaged daylight spectrum of “open sky”
These features assure reduction in glare, do not cause headaches from flickering, and make the high intensity of light enter the eye better from off angles and from a broader array of distances from the source.
1. Golden RN, Gaynes BN, Ekstrom RD, et al. The efficacy of light therapy in the treatment of mood disorders: a review and meta-analysis of the evidence. Am J Psychiatry. 2005;162:656-662.
2. Terman JS, Terman M, Lo ES, et al. Circadian time of morning light administration and therapeutic response in winter depression. Arch Gen Psychiatry. 2001;58:69-75.
3. Giedke H, Klingberg S, Schwarzler F, Schweinsberg M. Direct comparison of total sleep deprivation and late partial sleep deprivation in the treatment of major depression. J Affect Disord. 2003 Sep;76(1-3):85-93
4. Terman M, Terman JS. Treatment of seasonal affective disorder with a high-output negative ionizer. J Altern Complement Med. 1995;1(1):87- 92. Goel N, Terman M, Terman JS, et al. Controlled trial of bright light and negative air ions for chronic depression. Psychol Med. 2005;35 (7):945-55. 8 DR.