Does tryptophan cause weight gain? (7 factors)

In this article, we will discuss whether tryptophan causes weight gain. Furthermore, we will talk about the role of tryptophan in the body, related research findings, contributing factors, tryptophan-rich foods, and weight management strategies while using tryptophan.

Does tryptophan cause weight gain?

Tryptophan does not cause weight gain. Tryptophan supplements may cause weight loss in some individuals when taken in recommended doses because they control the appetite by increasing serotonin synthesis in the synaptic regions of the brain. 

Tryptophan is an essential amino acid which is an important constituent of the human diet. However, tryptophan is not synthesized in our bodies and has to be taken in the form of food or supplements. Tryptophan supplements may also be considered an effective therapy for depression and sleep disorders in some individuals (1). 

What is the role of tryptophan in the body?

Tryptophan has a significant role in the body by being involved in the synthesis of serotonin, melatonin, and other important compounds needed for normal body functions. Tryptophan affects various metabolic processes and immune functions. 

Tryptophan levels may also be used in the clinical setting for the diagnosis of various disorders. Tryptophan is used for depression and sleep disorders due to its involvement in the synthesis of serotonin and melatonin (1). 

Serotonin regulates various body functions including sleep, appetite control, mood, emotions, and the body’s stress response. Melatonin is involved in the regulation of the sleep-wake cycle (2). 

What does research suggest about tryptophan’s effects on weight?

According to research studies, when tryptophan is taken regularly in the form of a diet or supplement, may help in preventing overeating and promote weight loss. Tryptophan-rich diet gives a feeling of fullness and satisfaction by increasing serotonin levels in the brain.

However, when the levels of tryptophan exceed the recommended limits, tryptophan may cause some unwanted adverse effects. Therefore, it is important to be cautious while using tryptophan-rich diets or supplements (3). 

Another research study indicated that when tryptophan is given to such individuals who are obese or have a tendency to weight gain, may lose weight while using tryptophan. This weight loss may be temporary and might be reversed when the medicine is stopped. 

Other issues such as fatty liver, high blood sugar, or insulin resistance may also be resolved while using tryptophan supplements. Tryptophan may also affect certain other substances in the blood such as lowering cholesterol, or specific amino acids, but does not pose any harmful effects on kidneys or liver (4). 

Which tryptophan-rich foods affect weight?

The dietary sources of tryptophan may include tuna fish, turkey, chicken, bread, cheese, nuts, eggs, or chocolate etc. Incorporating these tryptophan-rich diets is necessary for a healthy lifestyle and weight management but these foods should also be taken in portion sizes to achieve the desired effect (5). 

Tryptophan-rich diet or supplements should not be taken in excess as they may cause some adverse effects. The usual adult dose of tryptophan supplements is 60mg and it is safe when taken for 3 months. However, your doctor may determine the suitable dose for you according to your specific needs (6). 

What other factors may contribute to weight gain?

The other factors that may contribute to weight gain may include:

  • Lack of physical activity in daily routine.
  • Poor sleeping pattern or lack of sleep.
  • Overeating or unhealthy eating habits. 
  • Side effects of certain medications such as Effexor, Pristiq, or others. 
  • Genetic factors or the tendency of weight gain. 
  • Health problems such as hormonal imbalances. 
  • Psychological issues or stress may make you overeat and gain weight (7). 

What are the weight management strategies while taking tryptophan?

The weight management strategies while taking tryptophan may include:

  • Avoid junk food and always eat healthy homemade food. 
  • Drink plenty of water throughout the day to flush out toxins from your body. 
  • Stay active and do some kind of physical activity such as yoga, aerobics, swimming, walking etc. 
  • Set realistic goals and achieve your targets step by step to lose weight effectively (8). 

In my opinion, tryptophan does not cause weight gain. Tyrptophan raises serotonin levels and control the appetite, as a result of this mechanism, tryptophan when taken in sufficient quantities, may reduce food intake due to feeling of fullness and satisfaction caused by sertonin. 


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