Vitamins, Minerals and Dietary Supplements
What is phenylalanine? Why do we need it?
Phenylalanine is an essential amino acid. Along with two
other amino acids, tyrosine and methionine, phenylalanine
helps the body produce adrenaline. It is also a precursor
for other proteins and enzymes, including norepinephrine,
epinephrine and dopamine.
Phenylalanine acts as an analgesic and antidepressant. It
also acts as an appetite suppressant by administrating the
release of an intestinal hormone that signals the brain to
feel satiated after eating. As an analgesic, it has been shown
to decrease back pain, toothaches, and pain associated with
migraine headaches. It has also been used to treat attention
deficit disorder, fatigue, Parkinson's disease and premenstrual
syndrome.
How much phenylalanine should I
take?
The amount of phenylalanine to be taken depends on the condition
being treated. For depression, some practitioners recommend
1-4 grams daily; for attention deficit disorder, 0.5 grams;
and for Parkinson's disease, 0.5-2.0 grams.
What are some good sources of phenylalanine?
What forms are available?
Phenylalanine is found in a variety of sources, including
almonds, avocados, bananas, brown rice, cheese, corn, eggs,
fish, lima beans, peanuts, pumpkin seeds, sesame seeds and
soy products. It is also sold as a supplement in tablet or
capsule form.
What can happen if I don't get enough
phenylalanine? What can happen if I take too much? Are there
any side-effects I should be aware of?
Phenylalanine deficiency can lead to a number of symptoms,
including slowed growth, apathy, muscle loss, apathy and weakness.
There are no known signs of toxicity from phenylalanine; however,
excessive amounts can cause hypertension and/or migraine headaches.
Patients already taking antidepressants should not supplement
with phenylalanine. It should also be avoided by women who
are pregnant or lactating.
References
- Coupland N, Zedkova L, Sanghera G, et
al. Response to pentagastrin after acute phenylalanine and
tyrosine depletion in healthy men: a pilot study. J Psychiatry
Neurosci 2001 May;26(3):247-51.
- Fox C, Marquis J, Kipp DE. Nutritional
factors affecting serum phenylalanine concentration during
pregnancy for identical twin mothers with phenylketonuria.
Acta Paediatr 2000 Aug;89(8):947-50.
- Ganther HE. Selenotyrosine and related
phenylalanine derivatives. Bioorg Med Chem 2001 Jun;9(6):1459-1466.
- Lee Y, Silverman RB. Rapid, high-yield,
solid-phase synthesis of the antitumor antibiotic sansalvamide
A using a side-chain-tethered phenylalanine building block.
Org Lett 2000 Nov 16;2(23):3743-6.
- Smith ML, Saltzman J, Klim P, et al. Neuropsychological
function in mild hyperphenylalaninemia. Am J Ment Retard
2000 Mar;105(2):69-80.
