This practical guide will help you get back to a low-protein diet with the PKU 'traffic light system'.
PKU nutrition system summary
The low-protein diet for PKU is often managed using a simple colour-coded system that helps you make healthy food choices.
"Red" foods: avoid due to excessive protein content
Foods to avoid:
- Meat: All types of meat, including beef, pork, chicken, etc.
- Fish: All fish, including shellfish and canned fish.
- Eggs: All types of eggs, including liquid pasteurized eggs.
- Cheese: all dairy-based cheese.
- Nuts and seeds: all kinds, including marzipan (almond paste).
- Flour-based foods: such as bread, pasta, and cakes.
- Soy: foods made from soy, such as meat substitutes.
- In addition, you should be careful with aspartame, a sweetener found in soda and other products, as it contains phenylalanine.
- Grain based foods: Rice and cereals
"Orange" foods: limited protein, measure for substitutions
Caution should be exercised with foods that are lower in protein.
Common "orange" foods include:
- Vegetables such as asparagus, snow peas and spinach.
- Dairy products such as cow's milk.
- Aquafaba (chickpea water).
Use food labels and your dietitian's personal lists to adjust your diet. The amount of protein you can tolerate is checked by your treating dietitian and measured in 'substitutions' (1 replacement = 50 mg Phe = 1 g protein).
"Green" foods: very low in protein, safe to eat
These foods can be eaten in normal amounts and offer variety in the PKU diet.
Examples of green foods:
- Most fruits: fresh, frozen, canned or dried (except for the orange list).
- Vegetables that are naturally low in protein.
- Sugars and sweeteners, except aspartame.
- Jams, syrups and sweets.
- Fats, oils, herbs and spices.
Be careful with vegetables coated with wheat or rice flour, for example in chips or wedges. These should be counted as substitute foods.
