The controlling and ONLY FAR you need to consider medically while flying
gliders is 14 CFR 61.53(b).

Allan

So now I am still confused. Do I read this FAR to say if you know you have a
medical condition but don't think it will interfere with your flying, fly. OR,
if you have a medical condition which would make you ineligible for a medical
certificate you cannot fly even in an operation not requiring a medical
certificate...

(b) Operations that do not require a medical certificate. For operations
provided for in §61.23(b) of this part, a person shall not act as pilot in
command, or in any other capacity as a required pilot flight crewmember, while
that person knows or has reason to know of any medical condition that would
make the person unable to operate the aircraft in a safe manner.