Hi Isabela
It's obviously your choice whether you want to tell the DWP, but it is one of your health conditions, so there's no reason not to mention it. No one should use it against you in the PIP process.
I have a family member who is obese, among other medical conditions, and the impact is felt on at least six of the PIP questions. So washing and bathing are limited because of their size. They need help to dress, their mobility is impaired, and they don't mix with other people because of it.
I'm not saying it is the same for you, Only you know how it impacts your daily living and/or mobility, so you talk about it where appropriate, keeping in mind the PIP criteria.
If you have any further questions, don't hesitate to ask.
BIS
Nothing on this board constitutes legal advice - always consult a professional about specific problems 
