Does tryptophan lower cortisol? (3 researches)

In this article, we aim to answer the query: “Does tryptophan lower cortisol?” Furthermore, we will talk about the role of cortisol in the body, related research findings, the role of tryptophan in cortisol management, and what to do if tryptophan does not lower your cortisol levels. 

Does tryptophan lower cortisol?

Yes, tryptophan can lower cortisol levels. Tryptophan is an essential amino acid that is required by the body to perform its physiological processes effectively. However, tryptophan is not synthesized by the body and has to be taken either in the form of food or supplements (1). 

Tryptophan has a significant role in the synthesis of serotonin, melatonin, and niacin, along with other important compounds. Tryptophan levels are also utilized in the clinical setting for the diagnosis of certain cognitive disorders. Tryptophan supplements can be used to treat depression, anxiety and sleep disorders (2). 

Tryptophan is involved in the production of serotonin and melatonin. Serotonin, a neurotransmitter in the synaptic regions of the brain regulates the behaviour, mood, appetite, emotions, memory, and the body’s stress response. Melatonin, on the other hand, regulates the sleep-wake cycle (3). 

What role does cortisol play in the body?

Cortisol plays many significant roles in our bodies including regulation of immune functions, stress, metabolic functions, and inflammatory responses. During stressful conditions, our bodies get activated due to the release of cortisol and it keeps the nervous system and body alert during such times. 

Cortisol is also involved in the regulation of sugar and proteins and provides the body with enough energy to deal with stressful situations. Cortisol increases the levels of sugar by triggering the liver to produce more sugar and break down proteins in muscles (4). 

What does research suggest about tryptophan’s impact on cortisol levels?

According to a research study, when the participants were given tryptophan, they had lower stress hormones in their blood levels. People who were more prone to feeling stressed and hungry during difficult times got better after taking tryptophan supplements and their appetite was also controlled (5). 

Another research study examined the effects of tryptophan on people having a particular gene which is affected by tryptophan. When patients with a specific genetic makeup were given tryptophan supplements, which made them go through a stressful situation, had lower stress levels compared to others (6). 

These effects of tryptophan on lowering stress levels are due to decreased cortisol production which keeps the body relaxed and calm during stressful situations. The research studies discussed here indicate that tryptophan is involved in lowering cortisol levels in the bloodstream ultimately managing stress. 

What is the role of tryptophan in cortisol management?

The role of tryptophan-rich diet and supplements was examined in a research study. The study indicated that when tryptophan-rich diets are given, behaviour during stressful situations might not be changed; however, such diets may reduce the levels of stress hormones in the blood due to the effects on cortisol production.

However, due to variation among individuals in their genetic makeup, response to tryptophan-rich diets may vary (7). Another study also concluded similar findings about tryptophan-rich foods. The lower stress levels are due to the effect of tryptophan on reducing cortisol levels hence making the body relaxed (8).

What to do if tryptophan does not lower cortisol?

If tryptophan does not lower cortisol levels, you may need some alternative antianxiety medications, such as Cymbalta, Celexa, Luvox, etc. However, individuals may vary in their response to tryptophan-rich diets or supplements, due to their genetic makeup and differences in physiological responses. 

In my opinion, tryptophan may lower cortisol levels and hence be involved in lowering stress levels. Several research studies have suggested that tryptophan-rich diets and supplements have shown a significant reduction in cortisol levels. 

However, if someone does not benefit from tryptophan supplements in reducing stress levels, then they should consult their healthcare provider. They may evaluate their current symptoms and recommend other treatment options as per their specific needs. 

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