Katie, 31 PKU
The Truth is people with PKU need to have a PHE-free protein source in their diet. A PKU protein substitute is a special modified protein source made specifically to help manage PKU and make sure that your low protein diet is nutritionally balanced.
The truth is PKU protein substitutes have changed a lot in recent years. PKU protein substitutes come in a variety of flavours, forms and styles. You can have a ready-to-drink protein substitute that you can take on the go, or a powder that mixes with a very small amount of water so you have less-to-drink. See our product pages for more information or speak to your dietitian to learn more about all PKU protein substitute options.
The truth is PKU protein substitutes come in different forms and various lower volume, more concentrated options are available. See our product pages for more information or speak to your dietitian to discuss the different options.
HONESTLY, IT IS NEVER TOO LATE. Regaining control over your PKU diet at any age can help reduce the negative effects PKU can have on you; such as tiredness, difficulty concentrating, and mood changes.
Dan, 30 PKU
Phenylketonuria (PKU) is a genetic disorder that a person inherits from both parents. PKU occurs due to a deficiency of the enzyme phenylalanine hydroxylase (PAH). This enzyme deficiency interferes with a person’s ability to metabolize or process the amino acid phenylalanine (PHE) into tyrosine (TYR), another amino acid.
Amino acids, like PHE, are the building blocks of protein found in food and the human body. Consuming too much PHE from food can lead to a toxic build-up of PHE in the blood and brain of a person with PKU and over time this can cause irreversible brain damage (especially seen in children). Presently, there is no cure for PKU, but it can be managed effectively with the combination of a low protein diet and intake of protein substitutes specifically designed for people with PKU.
Many of the problems associated with being off diet can be minimized or may go away once your blood PHE levels are back in an acceptable range.
A low protein diet is needed to avoid the dangerous build-up of PHE and the symptoms that can occur when PHE levels are high. See above where we talked about signs and symptoms of high PHE and/or low TYR levels. Many teenagers and adults with PKU report feeling better when on a low protein diet.
A low protein diet is a diet that is low in natural protein to make sure that you get just the right amount of PHE; not too much to cause high blood and brain PHE levels, but also not too little as some PHE is necessary for normal body functioning.
All foods (other than pure fat, oil and sugar) contain a certain amount of protein and therefore PHE. Meat, chicken, fish and dairy are examples of foods high in protein and PHE but other common foods such as bread, pasta, rice, potato, corn and peas also contain a fair amount of protein and PHE. Learning which foods are high in PHE and which are low will help with your long-term diet management.
However, just eating a diet low in natural protein will not meet the body’s requirement for protein. So, to meet total protein requirements, the PKU diet also needs the inclusion of PKU protein substitutes. PKU protein substitutes provide a ‘safe’ source of protein, as they contain protein but little or no PHE.
Most fruits and vegetables are naturally low in protein and should make up the bulk of the PKU diet. There are also special low protein foods, which are available on prescription, that have been modified to be lower in protein than their usual store-bought counterparts.
These special low protein foods, such as low protein pasta, bread, rice, cereals and baking mixes provide more variety and can make the PKU diet more appealing and interesting. If you are interested in trying some low protein foods or learning more about what is available, please visit the low protein section of our website or speak to your dietitian who will be able to request samples for you.
Your PKU protein substitute is your main source of protein per day. Look at it as a special protein shake that contains a modified protein source specifically designed for those with PKU. The protein is a blend of amino acids that contains very little or no Phenylalanine and is supplemented with Tyrosine, the amino acid that individuals with PKU can only make in small amounts. Your PKU protein substitute must be used as prescribed by your healthcare professional.
Your protein substitute will make up the majority of your daily protein intake. Your healthcare professional will be able to advise you on the amount that’s perfect for you and arrange a prescription for a protein substitute that suits your needs.
Protein substitutes all have different features, with varying formats, calories, volume and a wide range of different flavours.
Calories: Protein substitutes are available with varying amounts of calories, so speak to your healthcare professional about one that best suits your needs.
Volume: Many protein substitutes can be made up with varying amounts of water so you can have a smaller volume, more concentrated drink or a more dilute tasting larger volume drink, depending on your taste preference. Your dietitian or clinician will be able to advise you further on this.
Flavours: Protein substitutes come in a wide variety of flavours.
See the individual products in the product section of our website for more information on all the formats mentioned above.
If you would like any further information, please speak to your healthcare professional or email firstname.lastname@example.org.
Brendan, 38, accountant working in financial services
David, age 40
Katie, age 31
NOTE: The information provided on this page is for guidance purposes only and is in no way intended to replace the care, advice and medical supervision of your healthcare professional. If you have any questions about the information provided here, please speak to your doctor or dietitian.