A stye (or hordeolum) occurs when an eyelash follicle becomes infected.
Conjunctivitis is the inflammation of the delicate membrane that covers the white of the eye and lines the eyelids (the medical term for this membrane is the conjunctiva or the conjunctival membrane).
Sore, tired eyes, which tend to occur after focussing on objects at the same distance for a long time.
Near-sightedness, far-sightedness and astigmatism are examples of vision disorders known as refraction disorders. Other vision disorders include macular degeneration, cataracts and glaucoma.
A diet rich in lutein and zeaxanthin may be essential to healthy ageing. Naturopath Kate Ferguson reveals why.