Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. 

Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotransmitters (dopamine, epinephrine, and norepinephrine), as well as thyroid hormone and melanin, phenylalanine intake is important.

Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotransmitters (dopamine, epinephrine, and norepinephrine), as well as thyroid hormone and melanin, phenylalanine intake is important.

Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotransmitters (dopamine, epinephrine, and norepinephrine), as well as thyroid hormone and melanin, phenylalanine intake is important.

Phenylalanine is a precursor for the amino acid tyrosine, which is essential for making neurotransmitters (e.g. epinephrine, norepinephrine, dopamine) and thyroid hormone. Neurotransmitters are the chemicals that communicate between nerve cells in the brain. It can relieve pain, alleviate depression, and suppress the appetite. Low levels may indicate a stressful lifestyle, leading to memory loss, fatigue, and depression.

Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotransmitters (dopamine, epinephrine, and norepinephrine), as well as thyroid hormone and melanin, phenylalanine intake is important.

Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotransmitters (dopamine, epinephrine, and norepinephrine), as well as thyroid hormone and melanin, phenylalanine intake is important.

Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotransmitters (dopamine, epinephrine, and norepinephrine), as well as thyroid hormone and melanin, phenylalanine intake is important.

Phenylalanine is an essential aromatic amino acid that serves as the biochemical starting point for several critical compounds in the body, including the catecholamine neurotransmitters — dopamine, noradrenaline, and adrenaline. On the Neurotransmitter XL panel, phenylalanine provides valuable insight into neurotransmitter synthesis capacity, stress metabolism, and amino acid balance.

Because the body cannot produce phenylalanine, it must be obtained from dietary protein sources such as meat, eggs, fish, dairy, soy, and legumes. Once absorbed, phenylalanine is converted into tyrosine via the enzyme phenylalanine hydroxylase (PAH), a process dependent on the essential cofactor tetrahydrobiopterin (BH4), as well as iron and vitamin B6. Tyrosine then serves as the substrate for dopamine synthesis, which can subsequently be converted into noradrenaline and adrenaline.

Thus, phenylalanine is the first building block in the catecholamine biosynthetic chain, influencing motivation, alertness, focus, stress resilience, and energy.

Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotransmitters (dopamine, epinephrine, and norepinephrine), as well as thyroid hormone and melanin, phenylalanine intake is important.

Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. 

Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotransmitters (dopamine, epinephrine, and norepinephrine), as well as thyroid hormone and melanin, phenylalanine intake is important.

Final products include: DOPA, dopamine, norepinephrine, epinephrine, thyroid hormones, melanin, in TCA cycle, or 4-hydroxyphenylacetic acid.

Phenylalanine is a precursor for the amino acid tyrosine, which is essential for making neurotransmitters (e.g. epinephrine, norepinephrine, dopamine) and thyroid hormone. Neurotransmitters are the chemicals that communicate between nerve cells in the brain. It can relieve pain, alleviate depression, and suppress the appetite. Low levels may indicate a stressful lifestyle, leading to memory loss, fatigue, and depression.

Phenylalanine is a precursor for the amino acid tyrosine, which is essential for making neurotransmitters (e.g. epinephrine, norepinephrine, dopamine) and thyroid hormone. Neurotransmitters are the chemicals that communicate between nerve cells in the brain. It can relieve pain, alleviate depression, and suppress the appetite. Low levels may indicate a stressful lifestyle, leading to memory loss, fatigue, and depression.

The Phenylalanine/Tyrosine Ratio evaluates the body’s ability to convert phenylalanine to tyrosine; Conversion enzyme requires tetrahydrobiopterin (BH4), niacin (B3), and iron as cofactors.

The Phenylalanine/Tyrosine Ratio evaluates the body’s ability to convert phenylalanine to tyrosine; Conversion enzyme requires tetrahydrobiopterin (BH4), niacin (B3), and iron as cofactors.

The Phenylalanine/Tyrosine Ratio evaluates the body’s ability to convert phenylalanine to tyrosine; Conversion enzyme requires tetrahydrobiopterin (BH4), niacin (B3), and iron as cofactors.

Phenylglyoxylate is a Styrene metabolite.

Sources of exposure:

- Raw materials (benzene and ethylene) for the manufacture of styrene are supplied primarily from the petroleum industry.

- Used in the manufacture of synthetic rubbers, synthetic latex, polyesters, and plastic products.

- Automotive emissions, tobacco smoke, released from building materials, carpet backing. Low-level exposure may occure through ingestion of food products packaged in polystyrene containers.

- Packaging materials, toys, hobbies, crafts, house wares and appliances, electrical and thermal insulation, fiberglass, pipes, automobile parts, foam cups.