I will frame the perspective differently.

Assuming employer decide to terminate you on medical reasons, is that even allowed?
If it is allowed, then it make sense not to give the 'ammunition' to them by letting them know you are not healthy.

But then on the otherhand, if you are really not healthy and want to hide/lie to get a job then you are intentionally witholding material information that may legitimately cause you to to be fired.

But if employer openly states they do not discriminate against candidates for health, race, language, citizenship, etc . Then as a candidate, if you declare the 'unhealthy' status and is not offered a job.... you can complain to MOM or somewhere

So in a nutshell, why not just be trueful on your health status?