L-Phenylalanine: A Nootropic for Modulating BDNF Levels

Written on February 19, 2023 by | Reviewed by William Gallagher, MNeuroSci

L-Phenylalanine is one of the most popular nootropics available today.

It can be found in many pre-workout supplements and is used by people all over the world to enhance cognition.

But what does it do? And how can you use it to improve your mental performance?

Read on for more information about L-phenylalanine, including its effects on the brain.

What is L-Phenylalanine

L-Phenylalanine is a non-essential amino acid that is very closely related to L-tyrosine.

It can be synthesized by the human body either from dietary sources or from supplementary tyrosine.

In addition, it is present in many common foods such as dairy products and meat, although at much lower levels than its precursor, tyrosine.

Like many other nootropics, it is also available to purchase in the form of pills and supplements.

L-phenylalanine has several functions in the body, but it is most well known for its role in synthesizing proteins.

It plays an important part in producing hormones and neurotransmitters such as dopamine and serotonin, too.

L-Phenylalanine and BDNF Levels

In addition to its role in protein synthesis, L-phenylalanine also has a significant effect on the levels of brain-derived neurotrophic factor (BDNF).

This is a protein that increases the growth of new neurons throughout life.

It can be found throughout the brain but is especially common in the hippocampus.

This structure plays a key role in learning and memory formation.

As such, supplementing with L-phenylalanine can improve cognitive function on several levels.

What are the Effects of L-Phenylalanine?

L-phenylalanine is a natural mood enhancer and is generally considered to be non-toxic with no side effects.

Studies have shown that it can improve cognitive function when taken orally in doses ranging from 500 to 1500 mg per day.

Additionally, it has been demonstrated to be an effective antidepressant with no known side effects.

In addition, it can also improve athletic performance and has been shown to increase endurance during aerobic exercises such as running or cycling.

However, because of its role in protein synthesis, this supplement should not be taken alongside high-protein diets because this can lead to an excess of amino acids in the body.

How to Use L-Phenylalanine as a Nootropic

L-phenylalanine can be found in many pre-workout supplements.

These are products that aim to boost physical performance but also have a positive effect on mental function, too.

If you find it difficult to focus or concentrate during the day then adding phenylalanine into your diet could help immensely.

It is especially useful for those that have been diagnosed with ADHD or ADD.

In addition to being useful as a nootropic, L-phenylalanine also has several other benefits.

For instance, it is great for stimulating the production of melanin in the skin and can reduce chronic pain levels.

It may even help you lose weight if taken before exercise.

When purchasing phenylalanine, it is important to read the label and ensure that you are buying a product with pure L-phenylalanine as an active ingredient.

Do not purchase anything containing D-Phenylalanine because this form of the supplement is less effective - and can even be dangerous if taken in high quantities.

As with any other nootropic, it is important to use L-phenylalanine responsibly.

Begin by taking a lower dosage and see how you feel before slowly increasing the amount taken each day until you find what works for you.

In terms of dosage, I recommend starting at around 500mg and increasing this until you find the optimal amount to take.

Be aware that taking very high dosages may result in side effects such as headaches, nausea, or vomiting.

Does L-phenylalanine increase dopamine?

When it comes to L-phenylalanine, there is some debate as to whether it increases dopamine levels or not.

While scientific research has found that L-phenylalanine can increase the synthesis of this neurotransmitter in certain parts of the brain, others argue that this supplement does not affect dopamine at all.

As with many nootropics and supplements, the effects of phenylalanine will vary from person to person.

Some may find that it helps them focus and concentrate better while others feel nothing at all.

That being said, if we take a look at the scientific research done on this supplement so far, it seems to be largely positive.

Is L-Phenylalanine the Same as Phenylethylamine (PEA)?

Some people may wonder whether or not phenylalanine is similar to phenylethylamine (PEA).

Whereas this supplement increases levels of neurotransmitters such as dopamine and serotonin, phenethylamine mimics these same chemicals within the brain.

Both of these supplements are known to have a positive effect on mood and mental function, but there is one key difference between them: phenylethylamine occurs naturally in the brain while L-phenylalanine is an amino acid that must be ingested by way of food or supplementation.

Thus, although they both may help you focus and concentrate, phenylalanine is not the same as this natural compound.

What I like about L-Phenylalanine

I have taken L-Phenylalanine on and off for the past few years and I have found that it helps me focus more on the task at hand.

When I take this supplement, my mind is not as easily distracted by things around me so I can stay focused for longer periods.

The other thing I like about phenylalanine is its mood-enhancing effects - particularly when I am feeling tired or low in energy.

After taking this supplement, I tend to feel more motivated and energized which helps me get through the day without needing a nap!

Recently I've experimented with stacking L-Phenylalanine with L-theanine and I've found that the combination is great for helping me focus while also keeping my mind and body calm.

In Summary

If you're looking for a supplement to improve your focus and concentration - or simply want something that will help lift your mood, then L-phenylalanine is an excellent choice.

L-phenylalanine is known to boost neurotransmitters such as dopamine and serotonin which helps to increase motivation, focus, and mood.

In addition to this, phenylalanine is also a precursor for the production of adrenaline in the body - meaning that it can help you feel more energized in general!

While everyone's body responds differently to this amino acid, I highly recommend giving it a try to see if it helps enhance the results of your nootropic stack.

The best dosage of L-phenylalanine for me personally is around 500mg taken three times per day.

I usually take this supplement first thing in the morning, during lunchtime, and again mid-afternoon to help keep my energy levels up throughout the day.


What is L-phenylalanine used for?

L-phenylalanine is an amino acid that is used to treat depression, attention deficit-hyperactivity disorder (ADHD), Parkinson's disease, chronic pain, osteoarthritis, rheumatoid arthritis, alcohol withdrawal symptoms, and other medical conditions.

What are the benefits of L-phenylalanine?

L-phenylalanine has been used as a dietary supplement to treat osteoarthritis, depression and attention deficit-hyperactivity disorder (ADHD). It may also be effective in treating chronic pain associated with various types of arthritis.

Is L-phenylalanine safe?

Phenylalanine is generally recognized as safe when taken in amounts that do not exceed normal dietary intake (1500mg).

When should I take L-phenylalanine?

L-Phenylalanine is a supplement that works best when taken on an empty stomach or with fat to avoid making it harder for your body to absorb the amino acid. It is best taken early in the morning or mid-afternoon.

What foods contain L-phenylalanine?

L-Phenylalanine is found in most protein-rich foods, including meat, fish and dairy products. It can also be made by your body from another amino acid called tyrosine.