publicationmedia-verification" content="e1322166-9f17-48d2-91a8-6ef3e24e5faa

Phenylketonuria Diet Challenge – How did it go low protein?

I have just come to end of my low protein diet for phenylketonuria diet challenge for International PKU Day on 28th June. If you want to see why I was doing this, have a read here.

How Did I Get On?

It’s been an interesting, hungry, tiring, eye opening week. I have learnt so much about what my patients with PKU have to do on a daily basis. I was allowed 7g of natural protein a day. Here is an example of a daily meal plan:


Breakfast was low protein bread or gluten free bread, fruit, a cup of tea with low protein milk and my special drink. This drink contained all the parts of the protein I could have and all my vitamins and minerals. They are bitter and very strong tasting but as the week went on, they were easier to take.

Morning snacks were usually fruit and some low protein crackers.I would have my second special drink before lunch.


My lunches were not too bad but I found as the week went on I was finding it harder to eat them. I would have salads with low protein pasta. I used sweetcorn and a blob of houmous to get my allowed protein in. I tried to spice them up with olives, pickles, olive oil, coleslaw and balsamic vinegar.
Pudding was usually more fruit and a low protein biscuit or bit of cake my work colleague made.
It was like being pregnant again at work. I had to take tonnes of food to keep me going and get my energy in.
The afternoon was hard. I was hungry and tired. Fruit and copious amounts of carbs was getting tiresome. This was harder after work. I would have my final special drink, a cup of tea and some crackers to keep me going until tea.
My husband was awesome and cooked up low protein versions of our usuals. Above is a veggie curry with some rice to use up some of my 7g of exchanges. I did find I wasn’t always full. I would have berries for dessert and a couple of times used my last bit of protein for chocolate – only 15g but it was enough really.


I ate out once with my work colleague and this was fun and games. All vegan foods had chickpeas and lentils in them – protein! We would have needed scales to work out all the protein in chips and we probably went over what we should have had. We ended up with vegan salads which was ok. Having chips was the most filling part.

I carried on with my exercise and was surprised to find I had lots of energy. This may have been due to eating more frequently due to being hungry or eating more carbohydrates. This has made me think about my normal diet really. I need to eat a bit more to perform better in the gym.

Side effect-wise I have been very tired and “out of it” my hubby said. I’ve not engaged as much generally and I’ve been aware of being more snappy with the gremlin. She also reduced me to tears one day (not a good sign!) I wasn’t sure if this was due to hunger, tiredness or being deficient in the part of the protein I was cutting out! We don’t actually know.

I have learnt tonnes about the practical side of managing PKU. It is a difficult diet to follow long-term, especially for anyone going back on the diet. It is so easy to cheat, succumb to habits and to feel frustrated. Support, preparation and organisation are key to succeeding with the diet and I have the uttermost respect for the people that follow this diet and achieve so much everyday.



  1. June 28, 2015 / 8:58 pm

    I never even considered how much protein is in my usual diet until I read what you'be been eating and avoiding. This was really eye opening, especially when it comes to the difficulty of eating out! It must be a tough diet to maintain long term!

  2. June 29, 2015 / 5:53 pm

    I would really struggle with this as my diet is high protein low carbs, well done you for doing it. x

  3. June 30, 2015 / 8:10 am

    Wow, well done you for sticking to this as a way to learn what your client's go through. Any kind of diet restriction fills me with dread, as it can be so hard as a parent just to find time to eat healthily! In my freelance writing work I'm often writing about intolerances and food allergies and I'm always so grateful that these aren't issues for me or my family. #BloggingToJogging

  4. June 30, 2015 / 6:48 pm

    Well done!!! I've been doing low carbs, it's not easy!! xx #bloggingtojogging

  5. Laura Huggins
    July 1, 2015 / 10:13 am

    Wow! I didn't actually realise how much protein was in food. I eat more carbs than protein but I am sure even I would struggle on this diet!

    Laura x x x

  6. July 1, 2015 / 10:20 am

    I've been waiting to read your update. It's a fab thing you've done to experience the other side of what their diet is. It's very healthy in a way but does sound exhausting! Well done for sticking to it I can only imagine the effort it took to do. I think it's good for our bodies to push the reset button on things occasionally and like you said we learn things about or diet xx

    July 1, 2015 / 12:25 pm

    Sounds awful. I can't imagine having to do that long term. You'd have to really educate yourself- I had no idea half of the things you couldn't eat had protein in them. That's amazing that you're dedicated to your job enough to put yourself through that. And well done to hubs for helping out!

  8. July 1, 2015 / 2:03 pm

    Don't think I could do it. Good for you for sticking it out

  9. July 1, 2015 / 2:10 pm

    This sounds like a tough diet but good in you for doing it and getting through it #bestandworst xx

  10. July 1, 2015 / 4:45 pm

    This sounds incredibly hard! I've always found it really tricky to cut down on carbs, and felt I'd rather have eg veggie pasta than meat with veggies as it fills me up more, but I'm guessing there's a lot more protein sneaking into my diet than I think. #bestandworst

  11. Mrs Tubbs
    July 1, 2015 / 9:01 pm

    Wow, that sounds so hard. Well done for doing it for the whole week. I think I would have given up after the first day.

  12. Wander Mum
    July 1, 2015 / 9:35 pm

    Well done Sarah!! You did so well. I find it so interesting and it has definitely made me want to take a closer look at my diet. #bestandworst

  13. Silly Mummy
    July 2, 2015 / 12:29 pm

    Interesting to see someone do low protein, rather than all the high protein diets you hear about! & good to raise PKU awareness too! I tend to always follow a low protein, high carb diet as I prefer that.

  14. Silly Mummy
    July 2, 2015 / 12:29 pm

    Oops – #bestandworst!

  15. Mary Smith
    July 2, 2015 / 7:22 pm

    Sarah this is so interesting and what a great thing for you to do to be able to have more understanding, I must admit I had to google PKU (sorry) and was educated there. No way could I eat low protein unless it was for health reasons like that, as over the last couple of yrs ive built up to eating and cooking quite high protein meals for weight loss!
    Well done for sticking it out despite the side effects you experienced x

  16. Momma Boss
    July 3, 2015 / 7:30 am

    I think its really good that you've put yourself out to get a better understanding of your patients! Well done for sticking it out, I'm completely useless without sleep! I wish I could be sensible and eat better like you but I just love chips and chocolate, I hate fruit!

  17. July 3, 2015 / 5:55 pm

    Well done for sticking at it! Sounds like a tough one! Really intersting read

  18. Michelle Bailey
    July 6, 2015 / 8:25 pm

    Oh wow, well done you for sticking through it! I bet it was really interesting for you to experience it yourself and definitely a worthwhile sacrifice! 🙂 x