Cataract starts forming usually when you are 60 years old and
above. You won't be cured of cataract even if you consume Vit A.
You can only get rid of it by operation when the cataract has
matured.
Regarding your eye problems at night, maybe you would like an
optician or an optometrist to check your eyesight again. It maybe
because that your prescription for your glasses or contact lens is
not up-to-date. The reason being that, in the day, our pupils
constrict when it is bright. Thus, even if you have any error in
your prescription, you won't feel any difference as your pupils are
small due to the bright sunlight and thus, your resolution is good.
However, when night comes, your pupils are large, thus, if there is
any unwanted prescription not corrected, you may feel that your
vision is slightly blurry, thus, resulting in a later
response.
However, you may consider a professional advice from your eye
doctor.
Cheers.
