Second Nature Care Blog

Light at the End of the Tunnel for Depression

[fa icon="calendar'] Apr 4, 2020 12:58:00 PM / by Isadora Guggenheim


Are you depressed? Do you have SAD? There is light at the end of your tunnel.  The tunnel just happens to be your ear canal.  

A new study has shown that transcranial bright light into the ear canals has an antidepressant effect in the treatment of SAD.  89 patients (67 females and 22 males) received 12 minute daily doses of photic energy from light-emitting diodes of three different intensities for 4 weeks.  

Naturopathic medical scope of practice includes light therapy. I remember learning different ways of integrating light therapy into clinical practice. I have great SAD protocols with high quality nutraceuticals, intestinal microbiome make-over and I.V. ozone and amino acid therapies.

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What were the study findings?

All patients using low, medium and high doses had improvement with anxiety, reduction of depressive symptoms and better cognitive performance.  One in four patients experienced a mild adverse effect of headache, insomnia and nausea.  

The no difference response between different strengths of dose might be related to a saturation effect above a certain light intensity threshold.  

What causes SAD is unknown, but it could be due to phase-shifted circadian rhythms, altered neurotransmitter production and genomics (OPN4 gene variants). Some people have loss of energy, want to sleep more and have difficulty getting up, crave carbohydrates, gain weight, become more irritable, feel less social, experience daytime fatigue and lose concentration more easily. SAD is more common in colder climates with less light in the winter.  

How does bright light therapy work?  

The light stimulates Melanopsin, a retinal photoreceptor system in retinal ganglion cells.  Light-induced neural signals from retinal ganglion cells send messages through the retinohypothalmamic tract to the suprachiasmatic nucleus.  Light penetrates the human brain. Transcranial bright light therapy manages neural networks in the brain, improves cognitive performance, alleviates SAD and improves autonomic cardiovascular regulation.

Good news - Bright light therapy has a positive effect on immunoregulation in patients with rheumatoid arthritis.  Bright light therapy does not suppress melatonin secretion even if you do it in the evening.  

What's the RX for bright light therapy?

It is recommended to do bright light therapy early in the morning at 10,000 lux for 30 minutes.

Where can I get bright light therapy?  The bright light device used in the study is manufactured by Valkee Ltd. from Oulu, Finland. Click to Connect with Dr. G

Topics: Mood Disorders

Isadora Guggenheim

Written by Isadora Guggenheim

Isadora Guggenheim, ND, FNP, RN, MS, CNS, LMT, owner of Second Nature Naturopathic Care, LLC
For all appointments: Tel: 845 358-8385 Fax: 845 358-2963