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Phenylalanineis an amino acid, a compound your body uses to make proteins.
Aspartame is made of phenylalanine and anotheramino acidcalled aspartic acid.
However, people who havephenylketonuria(PKU) have to be cautious with how much they’re getting.

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PKU is a rare inherited genetic disorder that affects how the body processes phenylalanine.
Without this enzyme, phenylalanine builds up in the body and can become toxic.
If someone with PKU has too much phenylalanine in their body, it can be toxic to the brain.
As with other health conditions, earlier detection of PKU is better.
The primary treatment for PKU includes a lifelong diet that is strictly low in phenylalanine.
Alow-phenylalanine dietavoids high-protein foods like meat, dairy, nuts, and certain grains.
Additionally, products containing aspartame must carry a warning for people with PKU.
People with PKU must monitor their phenylalanine levels with regular blood tests and adjust their diet accordingly.
Sometimes, they may require tyrosine supplements since the amount of this amino acid may be low without phenylalanine.
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