Phenylalanine scientific facts

Phenylalanine (symbol Phe or F)[1] is a highly bio-available essential amino acid in humans, meaning though it is essential for your body, it is not produced naturally in your body. As a result, it must be attained either through supplementation or mother’s milk and other food sources including meat, poultry, fish, cottage cheese, lentils, peanuts, and sesame seeds.  There are 3 forms of phenylalanine: D-phenylalanine, L-phenylalanine, and the mix made in the laboratory called DL-phenylalanine. Among them L-phenylalanine is the essential amino acid found in proteins. Structurally, phenylalanine is a precursor for tyrosine, the monoamine neurotransmitters dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline), and the skin pigment melanin. Supplementation with phenylalanine has been presumed to have antidepressant effects. Phenylalanine has been studied for its effects on depression, pain and skin disorders.[

Phenylalanine Benefits

Phenylalanine supplementation is associated with numerous health benefits including brain health. As a nootropic, supplementing Phenylalanine helps you with a number of different positive effects including enhancing mood, relieving anxiety, increasing focus and concentration, improving motivation, etc. Phenylalanine is also an effective medication for skin disorders, feelings of depression and pain. This supplement may also enable the overall nervous system to operate more efficiently. However, though it is not common, it can be risky for the people who have the genetic disorder phenylketonuria (PKU). Supplementing Phenylalanine can keep you in a positive state of mind and lead to better emotional balance. The common health benefits of Phenylalanine include:Betters cognitive performance and improves memory and learning [4] Helps recover from depression [5] Improves mood [6] Helps people with attention deficit hyperactivity disorder (ADHD) [7] Helps people with Parkinson’s disease [8] Helps with a skin disease called vitiligo [9] Relieves chronic pain in patients [10] Alleviates the alcoholic withdrawal symptoms [11] Relieves rheumatoid arthritis [12] Improves weight loss [13] Helps people who have Alzheimer’s disease (AD) [14] Relieves anxiety [15]Phenylalanine is believed to act as an effective pain reliever. Evidences show that it is very effective for migraines and other headaches. Moreover, it seems to be quite effective for other types of pain including the lower back and neck, arthritis, and menstrual cramps. It is also helpful for different types of chronic pain, even those that begin with an injury or accident involving physical trauma.

How Phenylalanine works?

The body uses phenylalanine to make chemical messengers, but it is not clear how Phenylalanine might work. Phenylalanine supplement can cross the blood-brain barrier and enter into the central nervous system. Phenylalanine is an essential aromatic amino acid and plays a key role in the biosynthesis of other amino acids and is important in the structure and function of many proteins and enzymes. Phenylalanine is converted to tyrosine, used in the biosynthesis of dopamine and norepinephrine neurotransmitters. The L-form of Phenylalanine is incorporated into proteins, while the D-form acts as a painkiller. Absorption of ultraviolet radiation by Phenylalanine is used to quantify protein amounts.[16]  Phenylalanine is an essential precursor for dopamine, norepinephrine and epinephrine. When your dopamine levels increase, you can be better able to concentrate, organize your thoughts, and stay productive. Fourteen participants were given tests of spatial working memory, planning, verbal memory span and trial-and-error learning after acute Tyrosine and Phenylalanine Depletion (TPD), seven of whom also received positron emission tomography (PET) scans to measure changes in striatal dopamine (DA) levels.  Although TPD produced a clear reduction in Tyrosine and Phenylalanine availability to the brain, no impairments on any of the cognitive tests were observed. However, changes in spatial working memory and planning accuracy after TPD showed a highly significant relationship with the changes in striatal DA levels.[17]


Phenylalanine is generally considered to be safe and very well-tolerated. However, this supplement is associated with some negative effects that may include nausea, heartburn and headache. It may also cause anxiety and hyperactivity in children. You should avoid taking this supplement if you are breast-feeding or pregnant or you are taking any antidepressant at this moment. Phenylalanine should be avoided in people with certain inherited disorders like Phenylketonuria (PKU) that cause their bodies to build up too much Phenylalanine. People with such disorders can develop mental retardation, high blood pressure, stroke, and many other serious health issues if they consume phenylalanine. [18] Consult your physician or healthcare provider before adding a new supplement to your regimen.


There can be a wide range of effective dosages for Phenylalanine. 100 mg to 5,000 mg per day has been used by some clinical studies and research for several symptoms. 1,000 to 2,000 mg range of dosage for Phenylalanine daily has been a common dose for many users. However, you are advised to consult your healthcare provider to determine your appropriate dose. You can stack Phenylalanine supplements with Hordenine for more noticeable improvements in mood.