Navigating Life with PKU: A Dietary Balancing Act (PKU)

PKU is a rare genetic disorder that affects about 1 in every 10,000 to 15,000 newborns in the United States alone, according to the National PKU Alliance. PKU, or phenylketonuria, is caused by a deficiency in the enzyme needed to break down phenylalanine, an amino acid found in protein-rich foods. In simple words, it's a condition where eating your favourite foods, such as cheese pizza, hamburgers, and even a glass of milk, could harm your body. In case it is not managed properly, the condition results in phenylalanine building up in the blood, thereby leading to brain damage and other severe complications. 

Read below this article to know more about the role of proper dietary planning for people with PKU.

The symptoms of PKU can vary based on the severity of the condition. While it's typically asymptomatic in infants, the condition may develop signs within the first few months if left untreated. The common symptoms of PKU have been listed below.

PKU is basically caused by a mutation in the PAH gene, short for the enzyme phenylalanine hydroxylase. This enzyme is essential for breaking down phenylalanine, an amino acid found in protein-rich foods. And without it, phenylalanine accumulates in the blood and brain, leading to toxic effects.

PKU is inherited in an autosomal recessive pattern, which, in simple terms, means a child must inherit the defective gene from both parents to develop the condition. However, if only one parent passes on the gene, the child becomes a carrier without symptoms.

With routine newborn screening programs nowadays, PKU is usually diagnosed within the first few days of life. During this, a heel prick blood test measures the levels of phenylalanine in the blood. In case elevated phenylalanine levels are detected, additional tests, including genetic testing and phenylalanine tolerance tests, are conducted to confirm the mutation in the PAH gene and how much phenylalanine the body can handle, respectively.

The main aspect of treating and managing PKU is dietary management, which involves limiting phenylalanine intake while ensuring adequate nutrition. 

High-protein foods are the primary reason behind phenylalanine buildup. Here are some foods that people with PKU must avoid.

The PKU diet mainly comprises low-protein choices, which may include

However, you must note that PKU diets are personalised, and regular blood tests must be conducted to adjust your dietary intake.

When it comes to managing PKU, the only approach is to ensure a low-PHE diet. This way you can keep the PHE levels in your blood low to avoid severe complications, including intellectual disabilities and developmental delays. Since PHE is an important amino acid, you must consult with your doctor to recommend a personalized dietary care plan.