Firstly, it is preferable for you to be completely well when going for surgery. Hence, take more vitamin C-rich foods or supplements to boost your immune system. Vitamin C is also known to help tissue healing. If you have any flu, viral-like illness or fever, it may be advisable to postpone the surgery till you are well. This is to prevent any spread of infection to your eye.
Secondly, avoid taking any foods or medication that are known to cause blood-thinning as this may cause more excessive or easy bleeding during surgery. Examples of such foods include cordyceps, lingzhi and gingko; and medications would include Aspirin, Plavix, Warfarin and Ticlopidine.
Thirdly, we know that how dry your eyes are will affect how good your vision is after cataract surgery. This is especially so if you are getting a premium intraocular lens (toric or multifocal). So, in order to optimize your visual outcome, it is important to keep your eyes well lubricated with natural tears or to treat any underlying pathological dry eyes. Your eye doctor will be able to assess whether you need any special dry eye treatment.