Pumpkin seeds are high in zinc, good for the immune system.
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What is Phenylalanine?

Phenylalanine is an essential amino acid that plays a crucial role in the synthesis of proteins and neurotransmitters. It is an aromatic amino acid, meaning it contains a benzene ring in its chemical structure. There are two forms of phenylalanine: L-phenylalanine, which is the natural form found in protein-rich foods, and D-phenylalanine, which is a synthetic form that is not commonly found in food.

Why we need Phenylalanine?

Phenylalanine is necessary for the synthesis of proteins, which are essential for growth, repair, and maintenance of tissues in the body. Additionally, phenylalanine is a precursor for the synthesis of other important molecules such as dopamine, norepinephrine, and epinephrine, which are neurotransmitters that play a critical role in regulating mood, attention, and sleep.

Where is Phenylalanine found?

Phenylalanine is found in protein-rich foods such as meat, fish, eggs, dairy products, beans, and nuts. It is also found in artificial sweeteners such as aspartame, which is made up of phenylalanine and aspartic acid.

Daily requirements

The daily requirement for phenylalanine varies depending on age and sex. The recommended daily intake for adults is approximately 33 mg/kg of body weight. For infants, the recommended intake is higher, at around 100 mg/kg of body weight.

Phenylalanine deficiency

Phenylalanine deficiency is rare since it is present in many foods. However, individuals with a genetic disorder called phenylketonuria (PKU) cannot metabolize phenylalanine properly, leading to an accumulation of phenylalanine in the blood and brain, which can cause severe neurological damage. Infants are routinely screened for PKU at birth, and those with the condition are put on a low-phenylalanine diet to prevent complications.

Can you get too much Phenylalanine?

While phenylalanine is an essential amino acid, consuming too much of it can lead to health complications. Excessive intake of phenylalanine, particularly in the form of artificial sweeteners, can lead to headaches, dizziness, and even seizures in susceptible individuals. People with PKU should avoid consuming phenylalanine altogether, as their bodies cannot metabolize it properly.

Should I get Phenylalanine supplements?

In most cases, it is not necessary to take phenylalanine supplements, as it is present in many foods. Additionally, consuming too much phenylalanine can be harmful, particularly for individuals with PKU. However, some people may benefit from taking phenylalanine supplements, such as those with conditions that affect neurotransmitter synthesis.

Fun facts

Phenylalanine is one of the building blocks of proteins and is the precursor for the synthesis of other amino acids such as tyrosine.

Phenylalanine is used in the production of artificial sweeteners, including aspartame.

Phenylalanine plays a critical role in the synthesis of neurotransmitters such as dopamine, norepinephrine, and epinephrine, which regulate mood and attention.

Phenylalanine is an essential amino acid that cannot be synthesized by the body and must be obtained from food or supplements.

Individuals with PKU must avoid consuming phenylalanine, as their bodies cannot metabolize it properly.

Food high in Phenylalanine

This list shows food that are top sources of Phenylalanine and the quantity of Phenylalanine in 100g of food

1.54 g
1.44 g
1.36 g
1.19 g
1.1 g
0.911 g
0.87 g
0.87 g
0.807 g
0.785 g
0.725 g
0.681 g
0.668 g
0.665 g
0.593 g

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Fruit Vegetables Meat Dairy Eggs Bread Superfood Legumes Cereals Nuts and Seeds Seafood Other Spices and Herbs
Macronutrients Carbohydrate Fat Protein Water Fiber
Vitamins Thiamin (B1) Riboflavin (B2) Niacin (B3) Pantothenic Acid (B5) Pyridoxine (B6) Folate (B9) Cobalamine (B12) Ascorbic Acid (C) Vitamin A Vitamin K Vitamin E Vitamin D
Minerals Calcium (Ca) Iron (Fe) Magnesium (Mg) Phosphorus (P) Potassium (K) Sodium (Na) Zinc (Zn) Copper (Cu) Manganese (Mn) Iodine (I) Selenium (Se) Fluoride (F)
Amino acids Arginine Histidine Lysine Aspartic Acid Glutamic Acid Serine Threonine Asparagine Glutamine Cysteine Selenocysteine Glycine Proline Alanine Isoleucine Leucine Methionine Phenylalanine Tryptophan Tyrosine Valine