I would definitely advise against feeding cheese to your newt. In humans too much cheese can cause a variety of problems including constipation and increased cholesterol levels. There are so many natural foods that most newts will readily accept that there is no reason to feed cheese. Try earthworms cut into small pieces, small slugs, small feeder insects such as crickets and waxworms (which should be fed sparingly), pieces of fresh shrimp, whiteworms, and blackworms. Many species will also learn to accept soaked reptomin or tropical fish pellets. In any case feed a variety to help insure proper nutrition.
Chip