Everyone’s heard that low serotonin levels are associated with depression. While the serotonin theory of depression may be valid for some people, clearly not everyone with depression has low serotonin. However, we do know that for the majority of people, SSRIs (selective-serotonin reuptake inhibitors) help treat depression.
This has lead many people to wrongfully conclude that since a drug that elevates serotonin helps depression, the original problem must’ve been low serotonin. This is a problematic way of thinking about depression and one that I preach against. Tweaking other neurotransmitters is also capable of causing depression. My theory is that the biochemical signature of depression is subject to individual variation.
That said, it is clear that low serotonin can cause problems in psychological functioning. For you or someone else, the problem may be directly related to serotonin levels. If you have low serotonin, you may feel highly stressed, have sleeping issues, struggle with anxiety and/or panic attacks, and be more susceptible to depression.
Low Serotonin Levels (Symptoms)
Normal serotonin levels help regulate sleep, reduce pain, make us feel calm, and improve our mood. Abnormally high serotonin such as that observed in the cases of “serotonin syndrome” can detrimentally affect coordination, make us feel sick, and even cause death. Below is a list of symptoms that you may experience if you have suboptimal levels of serotonin.
- Anxiety: Those with high levels of anxiety generally tend to have low levels of serotonin. While serotonin usually isn’t the only neurotransmitter to blame for a person’s anxiety, increasing levels of serotonin are known to be an effective way to reduce anxiety. This is why those diagnosed with anxiety disorders or chronic anxiety tend to benefit from serotonergic medications.
- Carbohydrate cravings: If you have low serotonin, you may find yourself craving carbohydrates and/or other sweets. Carbohydrates are known to have an indirect effect on serotonin levels. This is because when your body ingests carbohydrates, allow tryptophan to become more available, which gets converted into serotonin. Craving carbohydrates is common even among those without low serotonin due to the fact that many carbs contain gluten, which is also addictive.
- Cognitive impairment: Serotonin may not be as important as dopamine for cognitive function, but it still helps. Serotonin has been found to enhance cognitive function and in some cases correct various aspects of cognitive dysfunction. Perhaps the biggest drawback associated with low levels of serotonin is that of poor memory consolidation.
- Depression: There is clear evidence that for many people, serotonin increases help to ward off depressive symptoms. This does not mean that everyone’s depression is only caused by low serotonin, but it does mean that low serotonin could be contributing to the problem. Many people find that when their serotonin levels are increased naturally or artificially, their depression subsides.
- Digestive problems: Studies have shown that serotonin signaling in gut plays a key role in the development of irritable bowel syndrome. Increasing levels of serotonin often help correct this condition and improve digestion. Those with many other symptoms on this list and digestive problems may find that low serotonin is partially to blame. Normal levels of serotonin tend to help promote healthy digestive function.
- Emotional sensitivity: Those with low levels of serotonin may also be more emotionally sensitive than those who aren’t. Some people with low serotonin may take subtle comments or jokes as personal attacks due to the fact that everything seems serious. Their low mood may result in them becoming increasingly emotionally sensitive.
- Fatigue: In some cases low serotonin can cause a significant degree of fatigue. If you feel consistently lethargic or tired, it could be a result of deficient serotonin levels. This fatigue is a common occurrence upon discontinuation from a serotonergic drug and often persists until serotonin levels are replenished.
- Headaches: There is a link between serotonin levels and headaches. The lower your level of serotonin, the more susceptible you will be to developing headaches. Severe headaches or migraines often improve when a person increases their serotonin level.
- Insomnia: Low serotonin is also associated with insomnia due to the fact that serotonin levels help with melatonin production. If a person has an abnormally low level of serotonin, their arousal may not decrease at the proper time of night in accordance to their circadian rhythm. This is likely a result of inadequate melatonin, stemming from low serotonin.
- Irritability: Another sign that your serotonin levels may be low is irritability. Minor annoyances may trigger full-fledged anger and you may find yourself snapping at others. Intense anger is often improved when serotonin levels are increased within a normal range.
- Libido changes: Most often people notice an increase in their libido (sex drive) when serotonin levels drop. Low levels of serotonin are associated with an increased desire to have sex and horniness, whereas higher levels of serotonin are associated with a decreased sex drive, but increased emotional connectedness or bonding.
- Light sensitivity: If it feels as if bright light hurts your eyes or you’ve become extremely sensitive to light, it could be a result of low serotonin. Since serotonin helps us stay calm and improves our mood, little things like bright sunshine may make a person with low serotonin levels feel uncomfortable.
- Low self-esteem: Another sign of low serotonin is that of low self-esteem or low confidence. If you have poor social confidence or can’t seem to stay calm in seemingly normal situations, low serotonin could be a contributing factor. This is why when some people take serotonergic antidepressants, they become more confident and social.
- Mood swings: It is common for people to experience mood swings when their serotonin is low. Acting aggressively or more emotionally sensitive in social situations are a couple of signs that serotonin may be a contributing factor to mood swings. If you find yourself angry, aggressive, depressive, and anxious – serotonin levels could be a factor.
- Obsessive thoughts: Those who have obsessive thoughts often feel trapped by their own uncontrollable thinking. These obsessive thoughts may become so severe, that a person feels as if they must act out compulsions (as seen in patients with OCD). Low serotonin can cause obsessive thoughts even among those without OCD. When the serotonin levels are increased, the obsessions may diminish.
- Overeating: As we know, there is a link between serotonin production and carbohydrate cravings. We also know that a person may feel depressed and/or anxious with low serotonin. Therefore as a means to escape these uncomfortable emotions and satisfy the “cravings” it may be more common for those with low serotonin to overeat.
- Pain sensitivity: There is an association between pain tolerance and serotonin levels. Those with higher levels of serotonin tend to have a greater ability to handle pain. Those with low levels of serotonin become increasingly sensitive to even minor pain. Handling pain can be difficult for someone with insufficient serotonin.
- Restlessness: Many people with low levels of serotonin end up feeling very restless or experiencing restless leg syndrome (RLS). Discontinuing a selective-serotonin reuptake inhibitor (SSRI) is known to make restless leg symptoms worse. Low levels of serotonin are known to make restlessness and increase the severity of RLS.
- Sleep problems: It’s difficult to sleep properly without adequate levels of serotonin. Low levels may cause anxiety and are associated with the stress response. This may mean that you aren’t getting proper restorative, deep sleep throughout the night. If your brain is in overdrive and you’re unable to relax, it’s probably going to make for a miserable night’s sleep. Plus melatonin is manufactured from serotonin. Without adequate serotonin to facilitate melatonin production, you may not feel sleepy when you should.
- Social withdrawal: Certain individuals may resort to isolating themselves from others and withdraw from social events as a result of low serotonin. Moderate levels of serotonin help promote calmness and agreeableness in social situations. If a person isn’t getting proper levels of this neurotransmitter, they may see no purpose in even trying to push through the social discomfort they experience.
- Sound sensitivity: Some people may become extremely sensitive to moderate or loud sounds in the environment. Modest or even low decibels may seem to bother those with lower than average levels of serotonin. Hearing these sounds may make an individual with low serotonin feel uncomfortable due to an increased stress response.
- Suicidal thoughts: Some people with low serotonin may experience suicidal thoughts as a result. Anyone that’s ever taken an antidepressant and gone through withdrawal may have experienced an increase in suicidal ideation as a result of low serotonin. Taking a serotonergic medication often helps decrease these thoughts.
- Weight gain: Due to the fact that low serotonin makes people crave carbohydrates, increases likelihood of overeating, saps a person’s energy, and makes them depressed – weight gain is an inevitable byproduct. Certainly not everyone with low serotonin is going to gain weight, but it may increase the probability.
How to Increase Serotonin Levels
Fortunately if you feel as if low serotonin is impairing your mental performance and ability to function in social situations, you can take some steps to boost it. Realize that when elevating serotonin levels, levels of other neurotransmitters may be indirectly affected. Also keep in mind that certain methods produce quicker results than others.
- Dietary changes: Making some simple dietary changes can elevate your serotonin levels. Consider planning to consume more foods that are rich in tryptophan (an amino acid that your body converts to serotonin). Carbohydrates will help make tryptophan more available, and thus can be an effective short-term strategy for raising serotonin. However, carbohydrates may be a problematic strategy in the long-run due to other effects (e.g. on glucose).
- Exercise: There is some evidence that consistent exercise may be effective at elevating levels of serotonin and improving its synthesis. It is believed to do this by increasing the availability to tryptophan as a result of fatigue. While the links between consistent exercise and serotonin are somewhat vague, researchers hypothesize a connection.
- Medications: The easiest way to increase serotonin levels is by taking a pharmaceutical grade serotonergic medication. Most commonly prescribed drugs that target the serotonin system are SSRIs (selective-serotonin reuptake inhibitors). These are effective for increasing the levels of extracellular serotonin in a short period of time. Other options include: SNRIs, atypical antidepressants, and tricyclic antidepressants.
- Sunlight: You may also want to consider increasing the amount of sunlight exposure you get during the day. Low levels of Vitamin D are associated with slower production of serotonin in the brain. If you want to increase the speed by which serotonin is produced, get yourself outside and under the sun. Supplementing Vitamin D is unlikely to yield the same effect as natural exposure.
- Supplements: There are several supplements that you could take if you suspect that your serotonin levels are lower than average. Assuming you’ve already made dietary changes, supplementing with either L-Tryptophan or 5-HTP could be beneficial. L-Tryptophan is likely safer than 5-HTP, but neither should be consumed over the long-term because the effects may be dangerous.
Conditions associated with Low Serotonin Levels
There are a variety of conditions that may be influenced by low serotonin levels. Keep in mind that not everyone with these conditions necessarily has “low serotonin.” However, many of these conditions are improved by increasing serotonin levels.
- Autism: It is thought that various cases of autism may be partially caused by dysfunctions in the serotonin system. Researchers believe that those with autism may have low levels of serotonin and mutations in the process of its transportation throughout the brain. Treatment for autism sometimes involves an SSRI medication to help increase serotonin.
- Anxiety disorders: Another condition associated with underproduction of serotonin is that of anxiety. Those who are frequently anxious are thought to lack serotonin to help promote calmness and relaxation when necessary. The low serotonin makes the person feel as if they are in constant “fight-or-flight” mode, and unable to reduce psychological or physical arousal.
- Eating disorders: Those with eating disorders often suffer low self-esteem, poor confidence, anxiety, and depression. There is a speculative link between low serotonin and dysfunction of its neurotransmission and eating disorders like anorexia, bulimia, etc. Many people with eating disorders find that taking an antidepressant to boost serotonin levels tends to help.
- Fibromyalgia: This is a condition characterized by body aches, muscle pain, and tenderness. Individuals diagnosed with this condition tend to be highly sensitive to pain and have a low threshold for pressure. It is thought that dysregulation of serotonin metabolism may be a contributor to this condition. Some people experience relief from certain symptoms by elevating their levels of serotonin.
- IBS: Serotonin plays a key role in the process of digestion and gut functions. Those with IBS or irritable bowel syndrome tend to not have enough serotonin for proper digestion. This leads to a person experiencing excessive diarrhea, abdominal pain, or flatulence. It is a very common condition affecting millions of people. Many people find relief from increasing their serotonin levels with an antidepressant medication.
- Major depression: Those diagnosed with major depressive disorder are thought to have serotonin deficiency. Although not everyone who is clinically depressed has a problem with serotonin, elevating low serotonin in an individual who is deficient tends to improve mood and eliminate depressive symptoms. SSRIs are considered a first-line treatment option for those with depression.
- Migraines: Studies suggest that those with migraine headaches tend to have lower than average levels of serotonin in the brain. Various antidepressants tend to increase levels of serotonin signaling, which reduces the likelihood that migraines will occur. Melatonin, a hormone that is strongly linked with serotonin levels is also related to migraines. For many people, boosting serotonin reduces headaches as well as the severity of the pain that they inflict.
- OCD: Obsessive compulsive disorder has been associated with lower than average levels of serotonin. Administration of an SSRI tends to be an effective treatment for reducing obsessive, intrusive thoughts as well as compulsions. While low serotonin may not be the only cause of this disorder, it has been thought to play an essential role.
- Sleep disorders: Some people with sleep disorders and wakefulness disorders have problems with serotonin levels. Pharmacological administration of serotonergic agents tend to improve sleep quality in those with sleep disorders. Low serotonin can manifest a variety of sleep issues including: insomnia, hypersomnia (excessive sleepiness), and poorer sleep quality.
- Undermethylation: Those with undermethylation have mutations in the MTHFR gene which leads to low levels of SAM-e, which helps donate methyl. It is estimated that between 15 and 20% of individuals who are undermethylators end up depressed, partially as a result of low serotonin levels. Fixing the methylation problem with dietary interventions and a supplement regimen can lead to normalized serotonin levels.
Have you ever had low serotonin levels?
If you’ve experienced low levels of serotonin, feel free to share some of the symptoms you’ve endured in the comments section below. While many people believe that they have low serotonin, believing is often different than the reality. Having neurotransmitter blood tests conducted can offer some insight as to whether you truly have low levels of this neurotransmitter, but even blood tests are thought to be a “crap shoot” in terms of accuracy.
Those that have taken serotonergic drugs such as antidepressants for awhile and stop cold turkey likely experience low serotonin during withdrawal. Most people that withdraw from an SSRI after consistent, prolonged administration have experienced some effects first hand of low serotonin. It takes time to replenish depleted levels, but with consistent effort, serotonin levels can be increased to a healthy range.
I believe that I dealt with low serotonin after playing “antidepressant roulette” (or serotonin roulette) for a couple years and then discontinuing treatment. This likely left me to face an antidepressant-induced chemical imbalance due to the fact that my brain had become used to receiving the extra serotonin, it developed tolerance to the drug, and then supply got cut off. There’s no way to know for sure whether it was low serotonin, but it would make logical sense that serotonin had something to do with it.