What is PKU?

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What is PKU?

I’ve been asked that question many times; by friends, colleagues, teachers, hospitality workers even medical staff. In fact there was a nurse sitting in at my last clinic appointment who wasn’t aware of PKU so the consultant asked:

“Polly, how would you describe what you have?”

Deep breath in: “I have inherited a mutated gene meaning my body cannot produce a particular enzyme which breaks down an essential amino acid. Amino acids are the building blocks of protein so I have to dramatically restrict the amount of protein I eat every day. If I eat too much protein, the amino acid builds up in my blood like a toxin affecting my neurological and central nervous systems. Ultimately too much protein in my food can lead to brain damage.”

At this point most people say “Woah, what did you call it again” Sometimes it is easier to say: “You know that warning on the back of soft drink cans ‘May contain Phenylalanine’? Well, it’s me they are warning.”

A restricted protein diet means people with PKU can NOT eat any :

  • Meat
  • Fish, including Shellfish
  • Eggs
  • Cheese (some new vegan cheese is ok, but not all vegan cheese)
  • Nuts and Seeds
  • Flour based foods (bread, cakes, biscuits etc.)
  • Soya & Tofu
  • Quorn
  • Any medicine or food containing Aspartame (an artificial sweetener)

Usually someone interrupts this list to exclaim “What do you actually eat?”
“Well,  I’m allowed to eat most but not all fruit and vegetables. There are medically synthesised pasta and rice substitutes which I get on prescription. There is also a medical flour so I bake my own bread etc. To supplement this diet I need to take prescribed supplements every day which make sure I get things like Iron and Calcium as I can’t have meat & dairy.”

And that in a nut shell is the PKU diet. There are many more resources online and a growing social media community fighting for new treatments.

NSPKU - The National Society for Phenylketonuria

This is a UK based organisation formed in 1973 to support people with PKU and actively promote new research and treatments. If you’d like to know more I’d suggest looking at their website: http://www.nspku.org/information/whatispku

or follow them on Twitter @NSPKU

My posts about PKU are all collected here.