Phenylketonuria, or PKU, is a rare inherited disorder in which babies are born without the ability to break down an amino acid known as phenylalanine, according to the National Institute of Child Health and Human Development. High levels of phenylalanine can cause mental retardation and birth defects. Phenylalanine is usually found in high-protein foods. A PKU diet involves the elimination of high-protein foods.
Low-Protein Foods
Patients with PKU should eliminate foods high in protein such as milk, eggs, chicken, red meat, fish, cheese, soybeans, nuts, beans and peas, according to the Marchofdimes.com. Patients with PKU should opt for low-protein foods such as cereals, whole grain breads and pasta. A dietitian may be helpful in helping families with PKU children choose the right sources of low protein. Regular blood checks are required to measure phenylalanine levels in the blood.
Fruits and Vegetables
PKU patients should consume a diet high in fruits and vegetables, according to Marchofdimes.com. Fruits and vegetables contain low amounts of phenylalanine. Examples of vegetables that a patient with PKU may consume include artichokes, broccoli, cauliflower, corn, cucumbers, eggplant, squash, tomatoes, pumpkin, pepper, asparagus, Brussels sprouts, beets, carrots, parsnips, celery, lettuce and cabbage. Examples of fruits that PKU patients may consume include bananas, apples, pears, apricots, cherries, peaches, prunes, plums, grapefruit, lemons, limes, oranges, tangerines, blackberries, blueberries and strawberries.
Special Formula
Protein is a very essential nutrient in the body. A PKU diet restricts the intake of high-protein foods. To ensure that patients receive protein, children and adults are given special phenylalanine-free formulas that provide protein and other essential nutrients. Lofenalac is an example of a formula made for infants with PKU. This formula can be used throughout life as a source of protein.
Fish Oil
PKU patients may benefit from fish oil supplements, according to MedlinePlus. Fish oil supplements help replace the long-chain fatty acids missing from a standard phenylalanine-free diet and may help improve neurological development. Other supplements that may be included in a PKU diet include iron and carnitine.
Aspartame
Patients with PKU should avoid aspartame, an artificial sweetener that is found in many sugar-free foods, according to the National Institute of Child Health and Human Development. When aspartame is broken down during digestion, high amounts of phenylalanine are produced in the byproducts. Examples of foods containing aspartame include sugar-free gum, candy, low-fat yogurt, chewable vitamins, cocoa mixes, diet sodas, breath mints, gelatin, cold medicines and pudding
