Phenylalanine: benefits and side effects

Published: 08/27/2012 - Updated: 02/04/2018

The strength, vitality and youthfulness of the body depend on a good balance of nutrients to keep it healthy. And phenylalanine is one of those essential components in our health. The phenylalanine is a neutral essential aromatic amino-acid and tryptophan. This is one of the more hydrophobic amino acid. It is known that this amino acid can block certain enzymes as enkephalinases, which are found in the central nervous system and that normally serve to degrade certain hormones called natural enkephalins and endorphins, morphine-like substances. These hormones have the function of acting as endogenous analgesic.

Favorable properties and reactions of phenylalanine in the body:

  • Analgesic: helps relieve or reduce pain.
  • Antidepressant: helps fight depression and elevates mood.
  • Feeling full: helps reduce appetite naturally.
  • Regulates heartbeat.
  • It is recommended to relieve some pain as in the lower back.
  • Useful to treat headache, menstrual cramps, muscle pain or those associated with rheumatoid arthritis and / or osteoarthritis.
  • Increases levels of endorphins.
  • Used in antidepressant treatments.
  • Stimulates brain functions.
  • Strengthens memory and learning.
  • Helps stimulate alertness and vitality.
  • Involves in the formation of collagen, making it very useful in problems of skin blemishes and as a preventative to avoid sagging skin and brittle nails or hair.
  • Contributes to form some neurohormones thus decreasing symptoms of some neurological diseases.

The lack or deficiency of phenylalanine in the body can cause:

  • Weak reflexes or reaction.
  • Heart rate altered.
  • Some diseases such as phenylketonuria (genetic disease that seriously affects brain during growth and development) and alkaptonuria, which is inherited and causes dark urine and predisposition to kidney stones.

Form of consumption, dosage and precautions

The phenylalanine appears in many foods we consume daily, so if you take a proper diet, including varied and quality foods, you don’t need to worry. The fenilanlanina has no side effects and is not harmful in adequate amounts; it may cause a mild laxative effect. However, when consumed excessively (as when taken through supplements or bodybuilders) it may cause certain alterations, so that’s why it should be consumed in moderation.

It’s better, of course, to get it from natural sources or taking supplements in moderation, without substituting natural food as vegetable oil, etc. (See details of obtaining sources below)

People who should avoid phenylalanine supplements:

People allergic to phenylalanine and pregnant as well, as higher doses in maternal blood can affect the fetus and cause growth retardation, microcephaly, mental retardation, heart problems, etc.

People with liver or kidney disease should be very cautious in the use of this amino acid, and not consume without professional guidance.

Phenylalanine-rich foods:

Phenylalanine is found mainly in protein-rich foods of plant and animal origin as:

  • Eggs, milk and animal products.
  • Phenylalanine-rich plant foods: asparagus, peas, lentils, peanuts, almonds, soy, nuts, etc.

Phenylalanine products or drugs to avoid:

  • All dietary foods that have sugar or artificial sweetener diet, which are terrible for the nervous system and the body's metabolism.
  • Antidepressants with phenylalanine, which ultimately affect kidneys and nervous system. It’s best to treat depression by natural ways, we must remember that you shouldn’t sedate depression; it’s a state of mind where the body wants to warn us about sadness or anger, dissatisfaction, lack of nutrients or poor nutrition, etc. You have to understand depression as a messenger and not a problem. A proper diet and a reconsideration of how we live and how we see life are the key to cure depression.
  • Avoid all refined products such as soft drinks or canned juices containing phenylalanine.

If you take a supplement with phenylalanine double check that the doses are appropriate and that is a quality and natural product, preferably organic. Always avoid giving these products in children or young people under 18. Do not forget to ask any questions to a professional and always remember that nature has all the nutrients we need, so a balanced diet and good quality food may be enough for you.

About the author
  • K. Laura Garcés G

    Writer, therapist and lecturer. She is a lover of natural medicine and the power of mind and emotions in body and life. In addition, he has studied nutrition and develops appropriate diets to support this healing process.She has written more than 1500 articles in magazines in Spain and Mexico, winner of two literature contests. Linkedin.