Phenylalanine is an essential amino acid, but the body does not make it, so it needs to be consumed through diet. Food sources include meats, eggs, soy products, and some nuts and seeds. Artificial sweeteners may also contain phenylalanine. Some individuals need to limit their consumption of this amino acid to maintain health and prevent adverse medical effects, and while some side effects can be alleviated by returning to a strict diet, others cannot, especially if an individual has not received treatment at birth for PKU. Before attempting to treat phenylalanine levels or side effects, talk with your doctor about safe ways to do so.
Stop drinking diet sodas, which often contain aspartame, which contains high levels of phenylalanine, according to the University of Maryland Medical Center. Look to see if any other drinks you typically consume contain aspartame. You might avoid foods sweetened with this additive, but may forget about other ways you consume it, which can cause side effects.
Eat a low-phenylalanine diet, especially if you have phenylketonuria, or PKU, a disorder in which an individual cannot break down phenylalanine. This can cause an excess of the amino acid to build up and may result in brain damage, if the level gets too high for too long. When people with PKU go off their special diets, poor concentration and memory problems can occur. This diet emphasizes fruits, vegetables, low-protein breads, juices and other foods that your health care team has recommended for the condition.
Take a fish oil supplement, also known as an omega-3 fatty acid supplement. Drugs.com states that long-chain fatty acids are usually missing from a phenylalanine-free diet, and omega-3 fatty acid supplements can provide the nutrients necessary to promote healthy neurological development. Other supplements may be necessary as well; ask your doctor about additional nutrients you may need.