Seasonal affective disorder (SAD) is a condition where 10% of the population  experience low mood, lethargy, and sleepiness during the autumn/winter months. Changes in the duration of day and night influences the body clock. Those experiencing SAD recover by spring/summer. Some SAD treatments include light therapy, CBT, and exercise which can alleviate the winter blues. These remedies for SAD are clinically proven to show benefit.
SAD and your brain chemicals
Your mood and mental state are a result of your brain’s chemical activity. The amount of light that enters your eyes (decreased in winter) influences two important brain chemicals including serotonin and melatonin. Their balance plays a major role in the way you feel during autumn/winter. Melatonin responds to darkness, with increased production during winter months . This contributes to low energy and sleepiness. Serotonin has a bigger impact on mood.
SAD and serotonin
Serotonin, your feel-good brain chemical, is intimately involved in regulating your mood. It is evidenced to vary between seasons. Serotonin levels are higher in summer compared to winter. Sunlight is one of the factors that keeps its levels high .
Tryptophan is an amino acid (protein building block) found in protein rich foods. Upon intake, tryptophan enters the brain and is converted to 5-HTP, which is then converted to serotonin (5-HT). Participants provided tryptophan-free drinks reported depressive symptoms, reinforcing the central involvement of serotonin in SAD .
The enzyme (compound that speeds up a chemical reaction) that converts tryptophan to 5-HTP needs Vitamin D to be activated . In the general population, vitamin D levels are at its lowest in winter  and this affects conversion of tryptophan to serotonin. To maintain optimal serotonin production from tryptophan, sufficiency of Vitamin D and tryptophan is essential.
5-HTP: a shortcut to serotonin
5-HTP, the precursor to serotonin is available in supplemental form as a safe way of increasing serotonin naturally. 5-HTP can freely enter the brain and is directly converted to serotonin. Evidenced supplements for SAD are yet to be developed. 5-HTP has been researched in mood disorders, with promising results. A review of 13 studies found that those supplemented with 5-HTP reported improvement in mood and lowered depression scores . Compared to an antidepressant, 2 weeks supplementation of 5-HTP demonstrated equivalent benefits in managing depression . Brain feed’s 100mg 5-htp is extracted and isolated from Ghanian Griffonia Simplicifolia seeds. 98% of the tablet is comprised of 5-htp making it the smallest, nutrient-dense tablet available and no unnecessary bulking agents. Read more about it here.
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