Circadian (7): Serotonin’s Secret Story
It is a major irony that we ignore sleep, screens, and indoor living in patients we suspect are struggling with serotonin deficiency, and instead rush to prescribe pills that stop its degradation. I understand that not everyone is ready to change their lifestyle for better health outcomes, but there will be some who appreciate knowing they have a healthful way to reverse their deficiency—especially when the "side effects" are all positive for the body’s experience. Serotonin is a major circadian hormone and neurotransmitter; as you have seen, you want it in the right concentration at the right time. This is definitely not what SSRIs are promised to do. With that introduction, we are going to explore more about serotonin today.
In the last article, I referred to serotonin as a "happy hormone." It was nice phrasing, but I was definitely inaccurate, as serotonin is not like dopamine at all. Dopamine is the happy, euphoric, reward hormone. Serotonin, on the other hand, is different. Think of it as a hormone for serenity and contentment. Here is the secret:
When you produce serotonin in the Raphe Nuclei, it exerts its action on your amygdalae. This is the section of the brain that associates stressful emotions with your daily experience; it processes your fight-or-flight response, often making small stressors look like emergencies. Well, when serotonin acts on the amygdalae, it dampens the noise and calms them down. Suddenly, the things that stress you out no longer become your preoccupation, and you can get on with life as normal again. You are back to the usual chatty, bright, and smiley person your loved ones have always known.
That is not all there is to it. On top of putting that blanket over your amygdalae, serotonin also fuels other parts of your brain such that you now have a bias towards positivity. Imagine seeing ambiguous faces as neutral or friendly rather than threatening. Essentially, it doesn’t just inhibit the over-association of negative emotions; it actually helps build social confidence. It sounds to me like a great alternative to alcohol.
Can it really be the miracle molecule? Absolutely—otherwise, the pharmaceutical industry would not have spent hundreds of billions researching this hormone since the 1950s. This daytime circadian hormone turns on endorphins and endocannabinoids, which make chronic pain bearable. These are the same receptors that your Lyrica and CBD oil target—all generated, sustained, and repeated by your internal programme, given the right circadian clock. Believe it or not, it all starts with light. Most doctors, living in a complex system of "which medication to give for what," find it very hard to follow my simple brain when I say this phrase.
I recently had the privilege of seeing a beautiful child with pain and posture difficulties. Part of my prescription was, of course, indirect sunlight, as serotonin will jumpstart endorphins and endocannabinoids. But what you might not know is that while serotonin is busy going down the back of the spinal column doing its pain-control job, it also runs down the front to stimulate the Type I muscle fibres responsible for posture. Has anyone else noticed that when we are feeling down or depressed, our shoulders slump and our heads feel heavy? That’s your answer. Serotonin helps your posture via the motor neurons it activates. The medical world sees the proof of this when certain patients on SSRIs develop restlessness, tremors, rigidity, and twitching—called extra-pyramidal symptoms—from artificially raising the level of this wonderful hormone too far. Another point against pharma, and countless points for nature.
Circadian biology is a solid science according to our contemporary knowledge. There was much speculation about it, but Hall, Rosbash, and Young sealed the deal when they were awarded the Nobel Prize in 2017 for research conducted more than 20 years prior. Again, as a 2011 graduate, the emphasis I received on circadian biology was quite mild. I remember being halfway through medical school when a student from Trinity College Dublin School of Medicine told me that it was indeed important. I don’t know how the Irish got it right, but since then, I have had my ears up for anything circadian.
Serotonin, being a circadian hormone, is well-studied by both scientists and the industry, and they are all in agreement about what it does to the human body. The divide really lies in the different approaches to raising serotonin levels. As is the case with hypertension, the industry’s flag planted on the peak is overshadowing other real and effective methods. I wish, for our patients’ sake, more doctors would continue their diligent medical school learning and integrate these insights into practice. Most, if not all, of what I have shared with you in the past year is conventional knowledge that is now mainstream in medical schools. Some of it is ancient, some of it is modern—all of it offers insight into our body’s potential for natural healing, provided we have enough serotonin in our brain to think clearly.