L-phenylalanine

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Other names for L-phenylalanine

DL-Phenylalanine (DLPA – a mix of D- and L- forms)
Free-Form L-Phenylalanine
Essential Amino Acid
I-phenylalanine
Phenylalanine
phenylalanine

Synopsis of L-phenylalanine

L-Phenylalanine is an essential amino acid, meaning it must be obtained through the diet, as the body cannot synthesize it. It plays a critical role in protein synthesis and is a precursor to several important compounds, including tyrosine, dopamine, norepinephrine, and epinephrine. These neurotransmitters are essential for mood regulation, cognitive function, and stress response.

L-phenylalanine is involved in the synthesis of thyroid hormones and melanin, the pigment responsible for skin, hair, and eye color. It is also necessary for the production of catecholamines, which help regulate mood, energy, and alertness. By converting into tyrosine, L-phenylalanine supports the production of dopamine, a neurotransmitter that is critical for mental focus, motivation, and pleasure.

L-phenylalanine is found in protein-rich foods such as meat, fish, dairy products, eggs, and legumes. It is also available as a dietary supplement for those who may have phenylalanine deficiencies or wish to boost cognitive performance and mood.

Historical Use
L-phenylalanine was first identified in the early 19th century as a key amino acid in protein synthesis. It became widely studied in the context of neurotransmitter production, particularly after the discovery of its conversion to tyrosine and its role in dopamine and norepinephrine production. The importance of L-phenylalanine in mental health and cognitive function was recognized as researchers explored its role in the synthesis of neurotransmitters.

In traditional medicine, foods high in phenylalanine, like meat and dairy, were valued for their role in nourishing the body and providing protein. However, L-phenylalanine’s specific use as a supplement for mental clarity, mood regulation, and neurotransmitter support has only gained significant attention in more recent decades, especially as a precursor for tyrosine and other catecholamines.

Modern Use
Today, L-phenylalanine is primarily used for cognitive support and mood enhancement, as well as in sports nutrition for its potential to improve exercise performance and mental focus. Some of its most common uses include:

  • Mood and cognitive support: L-phenylalanine is converted into tyrosine, which then produces dopamine, a neurotransmitter crucial for mental clarity, focus, and pleasure. It is often used as a nootropic to enhance cognitive function, memory, and mental alertness.
  • Mood regulation: Due to its role in the production of dopamine and norepinephrine, L-phenylalanine is used to support mood balance and alleviate symptoms of depression or low energy. It may help in managing mild depressive states by boosting catecholamine levels.
  • Pain management: L-phenylalanine is sometimes used as part of a pain management regimen due to its potential to help the body produce endorphins, which may act as natural painkillers.
  • Neurotransmitter support: L-phenylalanine is used in clinical settings to support individuals with neurotransmitter imbalances and cognitive decline.

L-phenylalanine is commonly available in capsules, tablets, powder, and is sometimes found in nootropic and sports nutrition products. It is also used in combination with tyrosine and other amino acids in mood enhancement and focus-boosting supplements.

Safety Considerations
L-phenylalanine is generally considered safe when taken in appropriate doses, typically up to 500 mg per day for cognitive support. However, individuals with a genetic disorder known as phenylketonuria (PKU) must avoid L-phenylalanine, as they lack the enzyme to metabolize it, which can lead to toxic levels in the blood and cause neurological damage.

Excessive intake of L-phenylalanine supplements can also lead to gastrointestinal discomfort, including nausea or headaches, especially when taken in large doses over extended periods. As always, it is recommended to consult with a healthcare provider before beginning supplementation, particularly for those with PKU or other metabolic conditions.

L-phenylalanine is used for these health conditions

Addictions (general remedies for) (Traditional)
Depression (Scientific)
Pain (general remedies for) (Scientific)

L-phenylalanine is used to support these body systems

Brain (Scientific)
Dopamine (Scientific)
Nerves (Scientific)
Specific Neurotransmitters (Scientific)

Products containing L-phenylalanine

Designs For Health Amino Acid Supreme™
Designs For Health Amino Acid Synergy
Thorne Amino Complex Berry
Thorne Amino Complex Lemon
Pure Encapsulations Amino-NR
Pure Encapsulations Amino Replete
Metagenics BioPure Protein® Powder
Pure Encapsulations CarbCrave Complex
Pure Encapsulations Cognitive Aminos
Pure Encapsulations DL-Phenylalanine
Pure Encapsulations Essential Aminos
Douglas Laboratories Free Form Amino
Klean Athlete Klean Essential Aminos + HMB®
Klean Athlete Klean Isolate ™
Douglas Laboratories Muscle Protect™ with HMB®
Pure Encapsulations NeuroMood Pure Pack
Pure Encapsulations NeuroPure
Metagenics Perfect Protein® Pea & Rice Chocolate Powder
Metagenics Perfect Protein Pea & Rice Vanilla Powder
Metagenics Perfect Protein Whey Chocolate
Metagenics Perfect Protein Whey Vanilla
Pure Encapsulations Phyto UltraComfort
Vitabase Super Fat Burner
Metagenics Ultra Glucose Control® Chocolate
Metagenics Ultra Glucose Control Chocolate
Metagenics Ultra Glucose Control Vanilla
Metagenics Ultra Glucose Control Vanilla
Metagenics UltraGI Replenish® Chocolate
Metagenics UltraGI Replenish Chocolate
Metagenics UltraGI Replenish Vanilla
Metagenics UltraGI Replenish Vanilla
Metagenics UltraInflamX Plus 360°® Chocolate/Orange
Metagenics UltraInflamX Plus 360° Mango
Metagenics UltraInflamX Plus 360° Mango
Metagenics UltraInflamX Plus 360° Orange
Metagenics UltraInflamX Plus 360° Original Spice
Metagenics UltraInflamX Plus 360° Pineapple/Banana
Metagenics UltraInflamX Plus 360° Pineapple/Banana
Metagenics UltraMeal Advanced Protein® Dutch Chocolate
Metagenics UltraMeal Advanced Protein French Vanilla
Metagenics UltraMeal Advanced Protein Plain
Metagenics UltraMeal Cardio 360°® Pea/Rice Chocolate
Metagenics UltraMeal Cardio 360° Pea/Rice Vanilla

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