Does tryptophan lower blood pressure? (5+ side effects)

In this article, we will explore whether tryptophan lowers blood pressure. Furthermore, we will talk about the related research findings, dosage recommendations, benefits of tryptophan-rich diets in lowering blood pressure, its side effects, and what to do if tryptophan does not help your blood pressure. 

Does tryptophan lower blood pressure?

Tryptophan can lower the blood pressure, especially in patients with mild to moderate hypertension. Tryptophan may impact blood pressure due to its effect on serotonin. Tryptophan is an essential amino acid which is not synthesized by the human body (1). 

Tryptophan is also known as a precursor of serotonin, as it converts into serotonin in the body. Serotonin helps to regulate sleep, mood, appetite, emotions, and the body’s response in stressful situations (2). Along with serotonin, tryptophan is also associated with melatonin production (1). 

What does research suggest about tryptophan and blood pressure?

According to a research study, tryptophan supplements may help to lower high blood pressure even after a single dose. However, tryptophan may not have any significant effect on people with normal blood pressure. 

The mechanism behind tryptophan lowering blood pressure is believed to be that tryptophan increases the serotonin levels in the brain by being directly involved in its synthesis (3). 

Another research study indicated that tryptophan when given to patients with mild to moderate high blood pressure may help to lower the blood pressure. This is because tryptophan helps to make more serotonin in the body and also does not cause any significant side effects (4). 

What is the recommended dose of tryptophan for lowering blood pressure?

The recommended dose for tryptophan for lowering blood pressure is decided according to your body weight by your healthcare provider. Dose recommendations of tryptophan may also be impacted if you are taking a tryptophan-rich diet along with supplements. 

According to clinical trial data, a higher dose of tryptophan 100mg/kg can lower blood pressure by 30 to 35 mm. Lower doses of tryptophan may have the opposite effect of raising blood pressure.

The effects of tryptophan may start showing after half an hour of the treatment; full effects may be shown after approximately an hour (5). However, people may have variations in their response to tryptophan in lowering blood pressure because everyone differs in their genetic makeup and physiological responses. 

Does a tryptophan-rich diet reduce blood pressure?

Tryptophan-rich diet may reduce blood pressure in some individuals. Research studies indicate that when tryptophan-rich diets are given for at least three weeks consistently, they may help to lower high blood pressure.

This effect of reducing blood pressure due to tryptophan-rich diet may continue for about 3 months of treatment. The mechanism behind this effect is found to be tryptophan’s effect on certain neurotransmitters in the brain including dopamine, norepinephrine, and epinephrine (6). 

However, it is important to note the effect of a tryptophan-rich diet may vary from person to person and the increased levels of tryptophan may pose some side effects. Therefore always consult your healthcare provider before taking a tryptophan-rich diet for longer periods. 

What side effects can tryptophan cause when used for blood pressure?

Tryptophan supplements used for lowering blood pressure may cause some side effects including:

  • Abdominal pain
  • Nausea
  • Vomiting
  • Constipation
  • Diarrhoea
  • Headaches (7)

If you experience any of these side effects and they persist or become bothersome, please reach out to yout healthcare provider. Tryptophan-rich diets or supplements should be used with caution with other medicines such as Luvox, Celexa, or others which can affect serotonin. Increased levels of serotonin due to combination of certain medications may pose a rare but life-threatening risk of serotonin syndrome. 

What to do if tryptophan does not lower blood pressure?

If tryptophan supplements does not lower your blood pressure, you may need some antihypertensive medications. Please consult your healthecare provider and only take antihypertensives if prescribed by your healthcare provider. 

In my perspective, tryptophan may lower blood pressure when used as supplements or through tryptophan-rich diets. However, lower doses of tryptophan might be associated with increasing the blood pressure and higher doses with lowering blood pressure. Always consult your healthcare provider before using tryptophan-rich diets or supplements for extended periods. 

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