Seratonin follow up – how to boost it

Last time I shared some wise words from a newsletter I follow about seratonin. Why re-do the research when someone’s already done it right? There are some really simple ways to protect and promote your seratonin levels and here are a number of them in no particular order.

1. This first one is timely as we head into months which have less sunlight, and research has shown a direct link to serotonin activity and seasonal affect disorder. The amount of serotonin in the brain shows seasonal variation when cadavers are studied and is reduced in the winter months. This also goes hand in hand with vitamin D in terms of seasonal affective disorder. They both need to be boldered as we hard into winter and less sunshine hours.
2. Unsurprisingly then, get some natural light. When the brain gets the natural light signal (in a place called the superchiasmatic nuclei, SCN, behind our eyes), it signals to the pineal gland to produce serotonin. This (as mentioned last week) is also a precursor to melatonin (our dark hormone). The ideal amount of time When the natural light is low, bright light therapy can help replace this, however it is thought that the natural light on the skin promotes serotonin production due to enzymes that are a key part of the serotonergic system that are located in the skin tissue. So it’s not just the eyes that enable us to instigate serotonin production, but it is being outside in the natural light as well. Early light is important, and recommendations of duration are quite variable, from as low as 10 minutes to as much as 30 minutes. Without burning (obviously), perhaps make an effort for 20 minutes a day. Get near a window if you can’t get outside. This (as a reminder) is less about vitamin D which we can’t synthesis easily in winter as the UVB rays aren’t strong enough, and more about the serotonin receptors in the eyes and on the skin.
3. Exercise regularly. There are three ways in which exercise boosts serotonin. Exercise increases blood flow and the availability of amino acids to be taken up by the muscles. Tryptophan (precursor to serotonin) is always in competition with other amino acids for the receptors that allow it to be taken up by the muscles, and almost always loses out to those amino acids (and other fuel, such as free fatty acids). This means that there is more tryptophan in the bloodstream comparatively, and more available to cross the blood brain barrier, allowing for an increase in serotonin production. Secondly, there is an increase in neural activity during exercise, including in the cells (raphe nuclei) responsible for releasing serotonin, which then binds to the receptors on postsynaptic neurons and activate various signalling pathways. Furthermore, the sensitivity of these postsynaptic neurons is heightened, so the effects of serotonin are greater. This is thought to be one of the ways in which people who have mood disorder notice improvements both during and after exercise. However, it is worth noting that serotonin has also been implicated with some side effects on the central nervous system, including increased fatigue, nausea and decreased motivation. It has been suggested the change in the ratio of serotonin to dopamine is responsible, but it’s unclear at this stage the exact mechanism. There is no single “best” type of exercise to enhance mood (with exercise, across the board, resulting in improved wellbeing and mood). Specifically with regards to serotonin levels, one study found that high intensity activity compared to lower intensity increased serotonin in a group of 121 young adults. Ultimately, though, do what you enjoy and do it often (for the wellbeing effects of exercise.)
4. Fermented foods are another important aspect of the diet that can help serotonin levels. I mentioned last week that 90% of serotonin is produced in the gut by our microbes. They need a healthy environment to thrive optimally, and fermented foods (along with resistant starch through vegetables) will enable this to happen in the right conditions for a healthy individual. Further, dark leafy greens and liver (pate, anyone) are rich sources of folate which is necessary for serotonin synthesis.
5. Practice gratitude – there is plenty of talk as to the benefits of practicing gratitude for increasing serotonin levels, and many articles (even some science-style ones) will say this. Yet there is no direct research that I can find to directly support that pathway. However, science doesn’t always reflect what we see in real life (and indeed, it is often behind practice) and those people who actively practice gratitude and do it daily certainly feel a positive shift in their wellbeing. Research does exist to show that there is an increase in the part of the brain that is associated with neural pure altruism, a reward that can’t be attributed to an external social status or even feeling good about doing something good.
6. And sleep. I would be remiss if I didn’t mention this. Sleep replenishes physiological and hormonal pathways, including those responsible for the production of serotonin. An ability to restore what is reduced during the day will always improve levels. Further, the relationship between serotonin and melatonin is bidirectional, and melatonin can increase serotonin levels also. So, when melatonin is high as it is during our sleep hours (peaking between 2-4am), this may enhance serotonin levels too.

Again gratitude to Mikki Williden who wrote and researched this stuff.