Does tryptophan decrease libido? (5+ factors)

In this article, we will explore whether tryptophan decreases libido. We will also discuss the role of tryptophan in the body, the link between tryptophan and libido, other factors affecting libido, and what to do if tryptophan decreases libido. 

Does tryptophan decrease libido?

Tryptophan may or may not decrease libido. Due to differences in the genetic makeup of individuals, people may respond differently. Tryptophan is an essential amino acid which can not be synthesized in the body and has to be taken through diet or supplements (1). 

Tryptophan is involved in the production of serotonin, melatonin, and other compounds, which are essential for the normal functioning of the body. Tryptophan is commonly found in some food sources such as oats, bread, chicken, turkey, cheese, milk, tuna fish, peanuts, bananas, and chocolates etc (2). 

Libido refers to the sexual desire. Some medications or supplements can affect the libido by lowering or increasing it, however, some other factors can also affect its levels (3). 

What role does tryptophan have in the body?

Tryptophan plays a significant role in the human body by being involved in the production of serotonin and melatonin. Tryptophan can also be used as a supplement in the treatment of depression, anxiety, or insomnia.

Serotonin is a neurotransmitter that regulates mood, appetite, emotions, and the body’s stress response. Melatonin is involved in inducing sleep. Reduced levels of serotonin or melatonin may disrupt normal cognitive functions of the human body (1). 

What is the link between tryptophan and libido?

The link between tryptophan and libido is the synthesis of serotonin in the body. When tryptophan is taken either in the form of a tryptophan-rich diet or through supplements, it increases the production of serotonin in the body which directly impacts the behaviour and mood. 

According to a research study, increased serotonin levels may cause problems with sexual activity in people taking a tryptophan-rich diet for longer periods or tryptophan supplements along with other medicines which may increase serotonin levels such as Celexa, and Luvox (4). 

What other factors affect libido?

The other factors affecting libido may include: 

  • Environmental factors including stress, depression, or anxiety can impact sex desire in both genders. 
  • Relationship problems with your spouse may also affect your libido. 
  • Side effects of certain medications such as Abilify, Pristiq etc. 
  • Underlying health conditions or lifestyle such as lack of exercise and unhealthy diet may affect your sex desire. 
  • Libido may decrease with age due to hormonal changes. 
  • Alterations in hormonal levels such as estrogen, and testosterone during different phases (5). 

What side effects can tryptophan cause other than decreased libido?

The common side effects of tryptophan may include:

  • Abdominal pain
  • Nausea
  • Vomiting 
  • Diarrhoea or constipation
  • Headaches (6)

If you experience any of these side effects while taking tryptophan, and they become bothersome, please inform your healthcare provider. 

What to do if tryptophan decreases libido?

If you suspect that tryptophan supplements decrease your libido, and it is causing discomfort and affecting your daily life, you should consult your healthcare provider. They will evaluate your overall health conditions.

Open and honest communication with your doctor helps to diagnose and treat your condition effectively. Your doctor will limit your intake of tryptophan if it is causing decreased libido. If needed they will prescribe you other antidepressants which best suit your needs. 

In my opinion, tryptophan may or may not cause decreased libido in patients taking it as a supplement for anxiety, depression, or insomnia. The levels of tryptophan should be maintained and dose of supplements should be carefully adjusted in the patients using tryptophan-rich diets or antidepressants that affect serotonin levels. Libido may also be affected by other factors such as environmental factors, health, and age. 

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