Does collagen reduce tryptophan? (3 researches)

In this article, we aim to answer the query: “Does collagen reduce tryptophan?” Furthermore, we will discuss the related research findings, the importance of tryptophan in the body, the effect of tryptophan deficiency, and collagen dose recommendations for tryptophan regulation. 

Does collagen reduce tryptophan?

Collagen may reduce tryptophan. Collagen supplements contain amino acids such as glycine (in higher amounts), methionine (in low amounts), or hydroxyproline, but these supplements lack tryptophan and hence do not provide tryptophan to the body. 

Collagen is an important protein in our bodies that is found in the extracellular matrix of our skin and cartilage. Collagen is also available in the form of supplements, which are made from the remains of animals such as bones or skin (1).

Tryptophan, on the other hand, is an essential amino acid, which means it can not be synthesized by the human body and has to be taken through foods like chicken, eggs, turkey, tuna fish, cheese, etc.

Tryptophan supplements are also available that can be used to treat depression or anxiety. Tryptophan is directly linked with the production of serotonin and melatonin in the body, and both of these compounds are involved in the regulation of various biological processes of the body (2). 

What does research suggest on collagen’s effect on tryptophan?

Research data on collagen’s effect on tryptophan is quite limited. However, according to a clinical study, it was suggested that collagen may reduce human plasma tryptophan levels by 74% as it lacks tryptophan and contains glycine, methionine, and hydroxyproline (3). 

Another study was conducted to evaluate the effects of temporarily reduced serotonin synthesis on the human body. Researchers administered mixtures of collagen peptides with and without tryptophan and found that a mixture without tryptophan significantly reduced tryptophan plasma levels in the body (4). 

What is the importance of tryptophan in the body?

Tryptophan is a significant component of the human diet but it is not synthesized in our bodies. Therefore, tryptophan has to be consumed through diet or supplements. Tryptophan levels can also be used by health practitioners to diagnose various cognitive disorders. 

Tryptophan when consumed, is then converted by some enzymes to serotonin, melatonin, niacin, and other important compounds in the body. Serotonin, a neurotransmitter found in the synaptic regions of the brain, is involved in the regulation of various biological processes of the body such as mood, sleep, behaviour, emotions, appetite, and the body’s stress response. 

Melatonin, another significant compound, regulates the sleep-wake cycle of the body. Tryptophan is considered an essential component of the human diet due to its strong association with serotonin and melatonin (2,5).

How does tryptophan deficiency impact overall health?

Lack of tryptophan may cause cognitive issues in some individuals because low tryptophan represents low serotonin levels. Serotonin has a significant role in regulating the cognitive functions in the human body and its low levels are associated with increased irritability, stress, anxiety, depression, sleep disorders, and other issues. 

Reduced tryptophan also affects our social behaviours, and disturbs mental and physical health. People may not find happiness in anything they do or experience. Raising serotonin levels through tryptophan-rich diets or supplements may affect overall mental and physical health positively by making people less depressed and socially active, hence improving overall life quality (6). 

What are collagen dose recommendations for tryptophan regulation?

There are no specific dosage recommendations for collagen for tryptophan regulation. If you are concerned about the use of collagen supplements, you should first consult your healthcare provider as low and high levels of tryptophan, both pose some adverse effects on the human body.

Higher levels of tryptophan may cause nausea, vomiting, diarrhoea, or constipation. If tryptophan levels are excessively increased when used in combination with certain medications which raise serotonin levels, such as Luvox, Celexa etc., they may cause an increased risk of a rare but life-threatening condition known as serotonin syndrome (7). 

As a pharmacist, I conclude that collagen may indirectly reduce tryptophan levels in the human body. This is because collagen contains amino acids such as methionine, and glycine, but lacks tryptophan. Before using any kind of supplement, it is better to consult about the dose and duration of these supplements, as low or high levels of tryptophan may cause some side effects. 

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