What type of food should my mom be cautious of, if she has high eye pressure?

None, really.: High eye pressure (iop) is not caused by foods. Certain consumables lower iop like alcohol, caffeine, pot, and diuretics. Oral Prednisone or steroids are a possible cause of increased iop. Nothing quite substitutes for a healthy diet high in anti-oxidants, green leafy vegetables, etc. These are all around good, but no food needs to be avoided for high eye pressure.

Caffeine: High levels of caffeine intake are the only proven linked food to high pressure.