Phenylalanine – Benefits, Foods and Uses

What is phenylalanine , food sources

What is Phenylalanine ?

L-Phenylalanine is an essential amino acid, which means that the body needs this ingredient and cannot be produced naturally.

Phenylalanine (which is converted to phenylethylamine) must be obtained through dietary supplements or through food sources including meat and dairy products, oat and wheat germ products.

For this supplement to be most effective, the body also needs vitamins B3, B6, C, copper and iron.

L-Phenylalanine as an amino acid helps to produce proteins in the body. There are also several different forms of this supplement: L-phenylalanine, D-phenylalanine, and DL-phenylalanine (the last combination of the two closest forms).



This dietary supplement is important for the normal functioning of the central nervous system.

It is also used for the formation and synthesis of various neurotransmitters such as epinephrine, dopamine and norepinephrine. All these chemicals are very important for the proper functioning of the nervous system.


Phenylalanine Effects

Although the specific mechanisms of action are still not fully understood, this dietary supplement is known to cross the blood-brain-barrier and enter the central nervous system.

This “barrier” is a protective function of red blood cells and the brain that prevents the entry of toxins, bacteria or viruses into the brain and nervous system. However, this barrier also retains many potentially useful compounds. The ability of it to cross the blood brain barrier is integral to its effectiveness as a cognitive enhancer.

One of the most important ways this dietary supplement works is thought to be the synthesis of neurotransmitters, especially dopamine, norepinephrine and epinephrine. Recent studies also show that it helps to produce melatonin (which is vital for controlling and regulating sleep and wake cycles).

This supplement is for tyrosine, another amino acid. Tyrosine itself is thought to be beneficial in anxiety and depression. It is also important for proper metabolic function and can help in reducing body fat.

Signals that transmit information from the neuron to the neuron are executed faster and more efficiently.



This essential amino acid found in protein-rich foods: dairy products, eggs, meat, fish, legumes, and more.

However, the source of phenylalanine, which needs to be restricted so for people with phenylketonuria, is any food product sweetened with aspartame, usually protein-free, such as a carbonated drink.

Phenylketonuria is used to label food products with information on the source of phenylalanine (even where it is not expected) and special labeling.



Phenylalanine appears to have a fairly wide range of effective doses.

Clinical trials used anywhere from 100 mg to 5000 mg daily. Typical users follow a dose of 1000 to 2000 mg per day.

It is also common to take a L-Phenylalanine supplement with hordenin, which is a compound that prevents the breakdown of this nootropic. The result is a longer exposure to phenylalanine and a marked improvement in mood.


Phenylalanine Side Effects

While this dietary supplement is generally considered safe and very well tolerated, there are some associated side effects. This is nausea, headache. This information should also not be used by people who are currently using antispirers and specific antidepressants (monoamine oxidase inhibitors – MAOIs). Always consult your doctor or a qualified medical professional before using this or any other dietary supplement.

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