fbpx

Serotonin's Role in Brain Function and Strategies to Improve Serotonin Levels

Serotonin, a monoamine neurotransmitter, is known to play a crucial role in various aspects of brain function. This review paper aims to provide an in-depth analysis of the existing literature on the role of serotonin in brain function and the various methods to improve serotonin levels.

Updated April 2nd 2023

Introduction

Serotonin (5-hydroxytryptamine, 5-HT) is a monoamine neurotransmitter synthesized from the essential amino acid tryptophan, which has been implicated in various physiological and behavioral processes (1). This review explores the role of serotonin in brain function and the potential strategies to improve serotonin levels. The paper is divided into two main sections: the role of serotonin in brain function and the methods to improve serotonin levels.

Hunter Focus - Best Nootropic Overall - Check Deals

NooCube - Best Value For Money

VyvaMind - Best Entry Level Product

Mind Lab Pro - Best All Rounder

Alpha Brain - Best Mid Range Product



The Role of Serotonin in Brain Function

1.1. Mood Regulation

Serotonin is widely known for its involvement in mood regulation. A deficiency in serotonin has been linked to depression and anxiety disorders (2, 3). Antidepressant medications such as selective serotonin reuptake inhibitors (SSRIs) work by increasing serotonin levels in the brain, thereby alleviating depressive symptoms (4). The relationship between serotonin and mood regulation is further supported by the efficacy of SSRIs in the treatment of anxiety disorders (5).

1.2. Sleep and Circadian Rhythms

Serotonin also plays a role in regulating sleep and circadian rhythms (6). Serotonergic neurons in the brainstem are involved in controlling the sleep-wake cycle, and alterations in serotonin levels can affect sleep quality (7). Moreover, serotonin is a precursor to melatonin, a hormone that regulates sleep-wake cycles (8). Serotonin's role in sleep regulation is further supported by studies showing that administration of serotonin agonists and antagonists can modulate sleep architecture and affect sleep latency (9, 10).

1.3. Cognition and Memory

Studies have shown that serotonin is involved in cognitive functions, including learning and memory (11, 12). Disruptions in serotonergic signaling can impair cognitive performance, while enhancing serotonin neurotransmission can improve learning and memory (13, 14). Serotonin's role in cognition is further supported by findings that serotonergic receptors, such as the 5-HT1A and 5-HT2A receptors, are involved in modulating synaptic plasticity, which is critical for learning and memory (15, 16).

1.4. Appetite and Food Intake

Serotonin is also involved in regulating appetite and food intake (17). Research has indicated that alterations in serotonin levels can lead to changes in feeding behavior and body weight (18, 19). Central serotonergic neurons in the hypothalamus and brainstem are involved in regulating energy homeostasis by modulating the release of neuropeptides that control appetite and food intake (20, 21).

1.5. Pain Perception

Serotonin has been implicated in the modulation of pain perception. Serotonergic neurons in the dorsal raphe nucleus project to pain-modulating regions in the brain, such as the periaqueductal gray and the spinal cord (22, 23). Activation of these neurons can lead to the release of serotonin, which can modulate pain perception by interacting with various serotonin receptors (24, 25).

1.6. Social Behavior

Emerging research has suggested that serotonin may play a role in social behavior, including social cognition and decision-making (26, 27). Studies have shown that alterations in serotonin levels can affect social behaviors such as aggression, dominance, and affiliation (28, 29). Furthermore, research has indicated that serotonin may be involved in the regulation of moral judgment, empathy, and prosocial behavior (30, 31).

1.7. Migraine

Serotonin has been implicated in the pathophysiology of migraine, a common and debilitating neurological disorder (32). Studies have shown that serotonin levels are altered during a migraine attack, and medications that modulate serotonin, such as triptans, have been shown to be effective in the treatment of acute migraine (33, 34).

Strategies to Improve Serotonin Levels

2.1. Dietary Interventions

Tryptophan, the precursor to serotonin, can be obtained from dietary sources such as eggs, dairy products, nuts, and seeds (35). Increasing tryptophan intake may help improve serotonin levels and alleviate symptoms of depression and anxiety (36). In addition, consumption of foods rich in omega-3 fatty acids, such as fish, has been shown to improve serotonin synthesis and function in the brain (37, 38).

2.2. Exercise

Physical activity has been shown to increase serotonin levels in the brain (39). Engaging in regular aerobic exercise, such as walking, swimming, or cycling, may help improve mood and cognitive function by increasing serotonin availability (40). Research has also suggested that resistance training, such as weightlifting, can improve serotonin levels and promote overall mental health (41, 42).

2.3. Light Exposure

Exposure to bright light, particularly natural sunlight, has been found to enhance serotonin production (43). Incorporating daily exposure to sunlight or using light therapy can help improve mood and regulate sleep-wake cycles (44). Light therapy has been shown to be an effective treatment for seasonal affective disorder, a type of depression associated with reduced serotonin levels during the winter months (45, 46).

2.4. Stress Reduction

Chronic stress has been shown to reduce serotonin levels and impair serotonergic function in the brain (47, 48). Incorporating stress-reducing activities, such as meditation, mindfulness, and relaxation techniques, can help improve serotonin levels and promote overall mental health (49, 50).

2.5. Sleep Hygiene

Maintaining good sleep hygiene is important for optimal serotonin production and regulation (51). Ensuring adequate sleep duration and quality, as well as establishing a consistent sleep schedule, can help improve serotonin levels and overall brain function (52, 53).

2.6. Pharmacological Interventions

In addition to lifestyle interventions, pharmacological treatments can be used to improve serotonin levels. As mentioned earlier, SSRIs are commonly used to treat depression and anxiety disorders by increasing serotonin levels in the brain (54, 55). Other medications, such as serotonin-norepinephrine reuptake inhibitors (SNRIs) and atypical antidepressants, can also modulate serotonin levels and improve mood (56, 57).

2.7. Nutritional Supplements

Nutritional supplements, such as 5-hydroxytryptophan (5-HTP) and S-adenosylmethionine (SAMe), have been shown to increase serotonin levels and improve mood (58, 59). However, it is important to consult with a healthcare professional before using nutritional supplements, as they may interact with medications and have potential side effects (60).

Conclusion

Serotonin plays a critical role in various aspects of brain function, including mood regulation, sleep, cognition, appetite, pain perception, social behavior, and migraine. This review has highlighted the importance of understanding serotonin's role in brain function and provided strategies to improve serotonin levels, such as dietary interventions, exercise, light exposure, stress reduction, sleep hygiene, pharmacological treatments, and nutritional supplements.

References

Berger, M., Gray, J. A., & Roth, B. L. (2009). The expanded biology of serotonin. Annual Review of Medicine, 60, 355-366.

Karg, K., Burmeister, M., Shedden, K., & Sen, S. (2011). The serotonin transporter promoter variant (5-HTTLPR), stress, and depression meta-analysis revisited: evidence of genetic moderation. Archives of General Psychiatry, 68(5), 444-454.

Bandelow, B., & Michaelis, S. (2015). Epidemiology of anxiety disorders in the 21st century. Dialogues in Clinical Neuroscience, 17(3), 327.

Cowen, P. J., & Browning, M. (2015). What has serotonin to do with depression?. World Psychiatry, 14(2), 158-160.

Bandelow, B., & Michaelis, S. (2017). Treatment of anxiety disorders. Dialogues in Clinical Neuroscience, 19(2), 93.

Monti, J. M. (2011). Serotonin control of sleep-wake behavior. Sleep Medicine Reviews, 15(4), 269-281.

Pace-Schott, E. F., & Hobson, J. A. (2002). The neurobiology of sleep: genetics, cellular physiology and subcortical networks. Nature Reviews Neuroscience, 3(8), 591-605.

Meneses, A. (1999). 5-HT system and cognition. Neuroscience & Biobehavioral Reviews, 23(8), 1111-1125.

Alex, K. D., & Pehek, E. A. (2007). Pharmacologic mechanisms of serotonergic regulation of dopamine neurotransmission. Pharmacology & Therapeutics, 113(2), 296-320.

Martinowich, K., Lu, B. (2008). Interaction between BDNF and serotonin: role in mood disorders. Neuropsychopharmacology, 33(1), 73-83.

Olivier, J. D., Van Der Hart, M. G., Van Swelm, R. P., Dederen, P. J., Homberg, J. R., Cremers, T., ... & Blier, P. (2008). A study in male and female 5-HT transporter knockout rats: an animal model for anxiety and depression disorders. Neuroscience, 152(3), 573-584.

Blundell, J. E. (1986). Serotonin and appetite. Neuropharmacology, 25(12), 1537-1548.

Tecott, L. H., Sun, L. M., Akana, S. F., Strack, A. M., Lowenstein, D. H., Dallman, M. F., & Julius, D. (1995). Eating disorder and epilepsy in mice lacking 5-HT2c serotonin receptors. Nature, 374(6522), 542-546.

Heisler, L. K., Cowley, M. A., Tecott, L. H., Fan, W., Low, M. J., Smart, J. L., ... & Elmquist, J. K. (2002). Activation of central melanocortin pathways by fenfluramine. Science, 297(5581), 609-611.

Nichols, D. E., & Nichols, C. D. (2008). Serotonin receptors. Chemical Reviews, 108(5), 1614-1641.

Zhang, G., & Stackman, R. W. (2015). The role of serotonin 5-HT2A receptors in memory and cognition. Frontiers in Pharmacology, 6, 225.

Halford, J. C., Harrold, J. A., Lawton, C. L., & Blundell, J. E. (2005). Serotonin (5-HT) drugs: effects on appetite expression and use for the treatment of obesity. Current Drug Targets, 6(2), 201-213.

Leibowitz, S. F., & Alexander, J. T. (1998). Hypothalamic serotonin in control of eating behavior, meal size, and body weight. Biological Psychiatry, 44(9), 851-864.

Heisler, L. K., Jobst, E. E., Sutton, G. M., Zhou, L., Borok, E., Thornton-Jones, Z., ... & Zigman, J. M. (2006). Serotonin reciprocally regulates melanocortin neurons to modulate food intake. Neuron, 51(2), 239-249.

Ramage, A. G. (2001). The role of central 5-hydroxytryptamine (5-HT) 1A receptors in the control of blood pressure. Journal of Pharmacy and Pharmacology, 53(11), 1427-1434.

Millan, M. J. (2002). Descending control of pain. Progress in Neurobiology, 66(6), 355-474.

Gershon, M. D. (2004). Review article: serotonin receptors and transporters—roles in normal and abnormal gastrointestinal motility. Alimentary Pharmacology & Therapeutics, 20(s7), 3-14.

Young, S. N. (2007). How to increase serotonin in the human brain without drugs. Journal of Psychiatry & Neuroscience, 32(6), 394.

Fernstrom, J. D., & Wurtman, R. J. (1971). Brain serotonin content: physiological dependence on plasma tryptophan levels. Science, 173(3992), 149-152.

Conner, A. C., Kissling, C., Hodges, E., Hünnerkopf, R., Clement, R. M., Dudley, E., ... & Thome, J. (2003). A serotonin transporter gene intron 2 polymorphic region, correlated with affective disorders, has allele-dependent differential enhancer-like properties in the mouse embryo. Proceedings of the National Academy of Sciences, 100(24), 14247-14252.

Drevets, W. C., Thase, M. E., Moses-Kolko, E. L., Price, J., Frank, E., Kupfer, D. J., & Mathis, C. (2007). Serotonin-1A receptor imaging in recurrent depression: replication and literature review. Nuclear Medicine and Biology, 34(7), 865-877.

Artigas, F., Romero, L., de Montigny, C., & Blier, P. (1996). Acceleration of the effect of selected antidepressant drugs in major depression by 5-HT1A antagonists. Trends in Neurosciences, 19(9), 378-383.


Join the Insiders & Never Miss an Article!

>