Definition
Light therapy is one of the non-drug treatment options for depression. The purpose of the therapy is to stimulate the human body with light very similar to daylight. This is believed to increase serotonin production and decrease melatonin production.
Serotonin is an endogenous messenger substance that is not present enough in people suffering from depression. Many antidepressants also try to increase the supply of serotonin in the area of the synaptic cleft. Melatonin however is a kind of antagonist of serotonin.
It is secreted more when it is dark and has a sleep-inducing effect. Elevated melatonin levels are said to have a depressive effect, i.e. to promote the development of depression. All in all, it can be said that according to recent research results, light therapy tidies up the hormone or messenger substance balance and thus is supposed to work as a positive counteractor against depression.
When should light therapy be used for depression?
Light therapy has the best chance of success with patients suffering from so-called seasonal depression, i.e. a depression that occurs mainly during the dark seasons of autumn and winter. Here the lack of daylight is probably one of the triggers for the development of depression. Accordingly, light therapy can be a good remedy against the genesis of depression. In the case of non-seasonal depression, the positive effect of light therapy has not yet been reliably proven, but it is nevertheless also used in patients suffering from non-seasonal depression, especially because of the few side effects and the overall rather positive general effect.
For which other diseases can light therapy be applied?
In addition to depression, there are other possible areas of application (indications) for light therapy. These include, for example, sleep disorders caused by disturbance of the day-night rhythm (for example, through shift work) and premenstrual syndrome (PMS).
Procedure of a light therapy
Light therapy should be performed as soon as possible after getting up so that the day-night rhythm is effectively controlled. The light clearly signals to the body that the day has now begun. In the evening hours light therapy should be avoided because otherwise the body is mistakenly suggested a wrong time of day, this can confuse the day-night rhythm.
Depending on whether the patient has the device at home or in a facility, it can be used daily in the first weeks, but at least 3-5 times a week. The duration of the individual light therapy sessions depends on the light intensity of the lamp and the distance of the patient from the lamp. At 10,000 lux light intensity, half an hour of light therapy per day is sufficient.
If the light intensity is weaker, the duration of the individual sessions is extended. The lamp should be placed at a distance of about 50 cm. If it is further away, the individual sessions should be extended.
The patient can read or listen to music during the session. It should not be looked directly into the light for long periods of time, but a glance at the light can do no harm from time to time. At the end of the session, the daily routine can be continued as normal.
Lamps for light therapy are now freely available and can be purchased over the Internet, electronics stores, discounters or drugstores. If you have now decided that you want to buy such a device, you are spoilt for choice, there are various devices in different price ranges. But what should you pay attention to?
One of the most important criteria when buying a light therapy lamp or light shower is the light intensity. The higher the light intensity, the shorter the daily sessions can be. With a light intensity of 10,000 Lux, a daily session of 30 minutes is sufficient at a maximum distance of 50 cm from the device.
If the devices have less light intensity, the therapy duration must be extended; information on this can usually be found in the manual of the respective device. At least 2500 Lux should be available for the device you are using. It should also be ensured that the device has a UV filter, as the light also contains radiation that is not good for our skin and eyes in the long term (this is also the case when we stay in the sun for a longer period of time). Such a UV filter filters out the “bad” parts of the light.Last but not least, the lamp should of course also be visually pleasing, nowadays there are many different designs so that everyone will surely find something that suits them.
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