High Doses of DLPA: Benefits vs. Dangers

DLPA is a nutritional supplement containing 2 different forms of phenylalanine. They are D- and L-phenylalanin.

Phenylalanine is an amino acid known as a “building block” for proteins. There are three different kinds of phenylalanine: D-phenylalanine, L-phenylalanine, and DL-phenylalanine, which is a mixture that is produced in the laboratory [1,2]. The function of the amino acid D-phenylalanine in humans is a mystery as it is not an essential amino acid.

The only form of phenylalanine that can be found in proteins is called L-phenylalanine, and it is an amino acid that is necessary for life [3,4]. L-phenylalanine can be found in relatively high concentrations in foods such as meat, fish, eggs, cheese, and milk.

Phenylalanine is used as a treatment for a variety of conditions, including vitiligo, alcohol withdrawal symptoms, depression, attention deficit hyperactivity disorder (ADHD), Parkinson’s disease, osteoarthritis, and rheumatoid arthritis.

Some people experiencing vitiligo choose to apply it straight to their skin.

Essential for Numerous Bodily Functions

Your body needs phenylalanine and other amino acids to manufacture the proteins in your brain, blood, muscles, and internal organs and virtually everywhere else.

In addition to that, phenylalanine is necessary for the production of the following molecules :[2]

• Dopamine.
  •  In addition to its role in motor control, memory, and learning, this neurotransmitter is essential for the functioning of the reward center in the brain [5].
• Epinephrine and norepinephrine.
  • In response to stressful situations, the body’s ability to either “fight or flight” depends on these molecules, which are essential to the process [6].
• Tyrosine.
  • Phenylalanine is a starting point for the production of this amino acid. Your body uses it to produce new proteins or convert them into other molecules, such as epinephrine, to carry out its functions [7].

The dysfunction of these molecules can lead to adverse effects on one’s health, such as depression [8,9].

Because your body needs phenylalanine to produce these molecules, researchers have looked into the possible connection between phenylalanine and major depressive disorders [10,11].

Health Benefits of Phenylalanine

Several studies have investigated phenylalanine’s therapeutic potential for various medical conditions.

According to some research, patients suffering from vitiligo may see an improvement in their skin pigmentation if they take phenylalanine supplements in conjunction with ultraviolet (UV) light therapy. The condition known as vitiligo is characterized by the loss of pigmentation in the skin [12,13,14].

Phenylalanine is also used in the production of dopamine, which is a molecule that is extremely important to both mental health and the treatment of depression [15].

Two-thirds of those who took a combination of the D- and L-forms of the amino acid reported improvements in their symptoms in an older, more limited study that was conducted in 1977 [16].

The study involved 12 people who were suffering from depression.

In more recent studies, low levels of the amino acid phenylalanine are associated with major depressive disorder.

On the other hand, findings from older studies don’t point to any obvious advantages. Because there hasn’t been much research done in recent years on the link between phenylalanine and depression, there needs to be more research done, and it needs to be of a higher quality [17,18,19].

Researchers have investigated phenylalanine’s possible effects on various conditions, including but not limited to vitiligo and depression.

• ADHD.
  • According to the most recent findings of relevant research, this amino acid does not contribute anything beneficial to treating attention deficit hyperactivity disorder [20].
• Parkinson’s disease.
  • There is some evidence, based on an older study, that phenylalanine could be helpful in treating Parkinson’s disease; however, further investigation is required. The effects of tyrosine on brain function and Parkinson’s disease have also been investigated; however, the findings have not been conclusive [21,22,23].
• Alcohol withdrawal.
  • According to a study conducted in 2011, taking a supplement containing D-phenylalanine and other amino acids may help alleviate the symptoms of alcohol withdrawal [24].
• Pain.
  • D-phenylalanine has been the subject of several studies, some of which have suggested that it may be effective in relieving pain; however, the research has produced conflicting findings [25,26,27].

Risks and Side Effects

Because it can be found in a wide variety of foods high in protein, the Food and Drug Administration (FDA) classifies phenylalanine as GRAS, which stands for “generally recognized as safe”.

The quantity of naturally occurring foods does not constitute a health risk for individuals who are in good physical shape. In addition, daily supplement doses of up to 12 grams are typically associated with minimal or nonexistent risk of adverse effects [28].

However, taking phenylalanine exactly as prescribed is important, and you should talk to a medical professional before incorporating supplements into your daily routine.

Patients who are taking antipsychotic medication and who also take phenylalanine may experience a worsening of the symptoms of tardive dyskinesia, a condition that is characterized by involuntary, repetitive movements [29,30].

Women who are pregnant or nursing should also avoid taking phenylalanine supplements because there is insufficient evidence regarding the safety of these supplements as well as the potential effects they could have over the long term.

In addition, people with phenylketonuria, also known as PKU, need to keep a close eye on how much of this amino acid they take in. Because of this condition, the body cannot metabolize phenylalanine effectively, leading to increased levels of the amino acid in the blood [31].

Phenylalanine levels in the blood that are dangerously high can cause severe brain damage, slowed growth, intellectual disability, and issues with transporting other amino acids to the brain [32,33].

In addition to epilepsy and hyperactive reflexes, PKU is linked to neurological conditions such as tics and tremors. As a result of the serious nature of this condition, screening for it is typically performed on newborns right after birth [35].

People with PKU are typically required to follow a specialized low-protein diet for the rest of their lives to control the amount of phenylalanine they take in through their diet.

Phenylalanine Rich Foods

The amino acid phenylalanine can be found in many high-protein plant and animal foods, such as meat, fish, poultry, and legumes.

Aspartame, an artificial sweetener frequently added to diet soda and other sugar-free foods, also contains it. Diet soda and other sugar-free foods often contain aspartame [36].

The following are some of the most common food sources of the amino acid phenylalanine:

• Diet products: flavored yogurts made with aspartame, diet soda,  candies, gum, and sugar-free ice cream. 
• Soy products: protein supplements, edamame, tempeh, tofu, soybeans. 
• Whole grains: wheat, barley, rye, oats, quinoa.
• Legumes: kidney beans, black beans, chickpeas, lentils.
• Nut butter: cashew butter, almond butter, peanut butter. 
• Seeds: sunflower seeds, hemp seeds, squash seeds, pumpkin seeds. 
• Nuts: walnuts, cashews, almonds, macadamia nuts, pistachios.
• Dairy: yogurt, cheese, milk.
• Eggs: egg whites, whole eggs.
• Seafood: lobster, shrimp, mackerel, tuna, trout, salmon.
• Poultry: goose, duck, turkey, chicken. 
• Meat: venison, lamb, pork, beef.

It is optional to choose foods based on the amount of phenylalanine that they contain in most cases. Consuming a wide variety of protein-rich foods throughout the day will ensure that you receive an adequate supply of phenylalanine and the other necessary amino acids and nutrients.

Bottomline: High Doses of DLPA

Phenylalanine is an essential amino acid that can be found in foods derived from both plants and animals.

Vitiligo, a skin disorder, might benefit from it, but research on its effects on depression, pain, and other conditions is limited. 

Those with phenylketonuria (PKU) need to keep their intake to a minimum to avoid potentially harmful side effects, although it is generally accepted to be safe for healthy people to consume.

Talk to your healthcare provider if you experience any uncomfortable symptoms after taking a phenylalanine supplement or eating foods high in protein.

They can perform a blood test to determine the levels of amino acids in your blood and help you choose the treatment that will benefit you the most.

Disclaimer: This article is only a guide. It does not substitute the advice given by your own healthcare professional. Before making any health-related decision, consult your healthcare professional.

Editorial References and Fact Checking

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