Serotonin Deficiency: What Is Causing Your Low Mood?

Serotonin Deficiency: What Is Causing Your Low Mood?

February 8, 2019 0 By Ben Yearwood

In my last post on CBT, I talked about the ABC model for actively changing your beliefs.

Today, I’m going to go in a slightly different direction and look a little bit more into the neuroscience of disorders such as depression and anxiety.

As part of my CBT qualification, I’ve been researching various topics in psychology and neuroscience. So, in this blog post, I will be sharing information on how serotonin deficiency could be causing you to have a low mood.

I encourage you to find out as much as you can in every subject of self-improvement. It won’t all be self-help, spirituality and such subjects. Sometimes, taking a deeper dive into the workings of the mind and brain can give you a little more insight than a self-help book.

So, to begin, we should answer the first big question.

What Is Serotonin?

Serotonin is most commonly known as “the happy chemical”. Its main purpose is that of a chemical transmitter. It affects everything from the regulation of emotions down to fine motor skills. However, it has a much more complex role than simply controlling whether or not an individual is happy or not.

As well as controlling states such as anxiety, happiness or general mood, it also plays a role in sleep. It acts as a precursor to melatonin which regulates the sleep/wake cycle. It also has a hand in controlling sex drive, digestion, appetite and much more.

Serotonin (or 5-hydroxytryptamine) can be found in blood platelets and the central nervous system. However, 95% of the body’s serotonin is found within the gut.


What Is The Role of Serotonin?

As stated already, serotonin has a very complex role.

One of its main roles would appear to be the natural regulation of moods. Low levels of serotonin can cause certain mood related disorders such as depression and anxiety.

However, it also plays a role in learning, memory formation and motivation. This chemical is of great importance not just to the brain and the body, but for life as a whole.

However, serotonin is only at it’s most effective when there are the right amounts of it in the body.

Too much can lead to serotonin toxicity which can typically occur when an individual is using certain medications such as selective serotonin reuptake inhibitors (SSRIs). If not treated correctly, serotonin toxicity can prove to be very hazardous and, in some cases, even fatal.

But, the more common issue is not having enough serotonin in the body and the numerous side-effects which have been linked to that.


What Happens When There Is A Serotonin Deficiency?

Whilst a serotonin deficiency can result in digestion problems, fatigue and weight gain amongst other things, the most common side effects are more psychological rather than physiological.

The most well-known side effect of a lack of serotonin is depression which is often linked with the deficiency. However, it is not yet clear whether depression is caused by a lack of serotonin or if depression causes the body to produce less serotonin. In this and other things, it is not fully understood what the role of serotonin is in these systems.

A lack of serotonin has been noted to be either causally linked or, at least, correlated to eating disorders, post-traumatic stress disorder and social anxiety disorder and much more including general anxiety and aggression.

It is important to reiterate that the way serotonin is linked to any of the previous has yet to be conclusively determined. There have been a lot of different results in studies related to serotonin deficiency.

For example, a 2007 study found that a lack of serotonin caused depression in female participants. However, men showed no such mood alterations and, in fact, became more impulsive.

Serotonin deficiency can be treated with medication which acts to increase the amount of serotonin the brain can absorb. These are called Selective Serotonin Reuptake Inhibitors (SSRIs) and are quite effective when it comes to adjusting a serotonin deficiency.

However, it should be noted that certain therapeutic interventions have been shown to increase serotonin. So, medication is not the only tool with which a serotonin deficiency could be addressed.



Though it is unclear exactly what the role of serotonin is, it’s effects are well-researched and well-known.

Like everything else in the human body, it must be balanced. Too much and there is a risk of serotonin toxicity. Too little and the risk becomes serotonin deficiency which is linked to depression, anxiety and much more.

Please follow and like us: