Try eating more protein and a little fat early in the day and at lunch. Eliminate the bread and have the lunch tuna wrapped in a lettuce leaf or two. A few black olives are a good side option unless you have been told to watch your salt intake. Salads without protein will NOT satisfy hunger. Protein is the key. At dinner try going heavy on non-starch vegetables. Anything high in carbohydrate or sugar will trigger hunger. Also drink water throughout the day, plain or with some lemon squeezed into it for flavor, as it helps to create a feeling of fullness and also hydrates.