Some people with liver disease must eat a special diet. This diet helps the liver function and protects it from working too hard. Proteins normally help the body repair tissue. They also prevent fatty buildup and damage to the liver cells.
Advise is a verb, and advice is a noun. So advice is what is given, while the act of giving advice is called advising (or to advise).
Taking and giving advice. The central difference between advice and advise is that the spelling advice, with-ice at the end, is the standard English spelling for the noun, but *never* for the verb.