Winters are long and hard and for some people, that means changes in mood and bouts of depression. 16.2% of the US population experiences seasonal depression disorders. Seasonal Affective Disorder (SAD) is a type of depression that’s related to changes in seasons — SAD begins and ends at about the same times every year. Most people experience symptoms starting in the fall continuing into the winter months. According to the Mayo Clinic, one of the most effective treatments for SAD is light therapy (photobiomodulation therapy or PBM).
There are 4 known factors that cause Seasonal Affective Disorder (SAD); circadian rhythm, serotonin levels, melatonin levels, and BDNF (Brain Derived Neurotrophic Factor). The reduced level of sunlight in the fall and winter may cause winter-onset SAD. The lack of sunlight disrupts your internal clock and leads to feelings of depression. A drop in seratonin, a neurotransmitter that affects mood, can trigger depression too. The change in season also affects your melatonin levels, affecting your sleep pattern and ultimately your mood. That’s where light therapy, also known as photobiomodulation (PBM), helps reduce and eliminate those effects. Finally, red light induces BDNF expression. BDNF builds up and sustains neurons, especially myelin sheath. The lack of BDNF causes depression and neurological symptoms, causes memory problems, lowers pain threshold, causes sleep deprivation and mental stress and increases appetite. Damages in myelin sheath can cause irritation, depression, anxiety and brain fog.
Photobiomodulation (PBM) utilizes red and infra-red light to improve mood and relieve symptoms of SAD. Red light is chosen because its penetration through tissue is maximal due to lower scattering and absorption by tissue chromophores. The absorption, scattering and chromophore concentrations of skin, melanin and red cell hemoglobin, are fundamental properties of tissue that can provide essential information for many aesthetic, therapeutic, and diagnostic applications.
The Light Doctors utilize PBM as a form of therapy to increase antioxidants, reduce inflammation, increase GSH (glutathione), slow cell death, and reduce serum cortisol levels. Photobiomodulation is an effective antidepressant strategy for the prevention of psychopathological and behavioral symptoms induced by stress.