Hi! I went on the Triumph this past year, which is a sister ship to the Destiny. I also do Weight Watchers, but do not follow it very well during cruise week!!!!!! Anyway, we usually eat at the buffets during the day, and eat in the dining room at night. At the lunch buffet they have a WONDERFUL salad bar with fat-free dressings. They also have fresh fruits. The turkey sandwiches at the deli are great. They also have grilled chicken sandwiches at the outdoor grill. The "serve yourself" frozen yogurt (chocolate, vanilla, or twist) is terrific!
For breakfast, they have fresh fruit, English Muffins, or toast, and other healthy things.
Weight Watchers has taught me to eat pretty healthy, so the fattening "saucy" foods don't even appeal to me anymore. At dinners they serve several types of seafood or even a lean filet mignon. You can also get grilled chicken for dinner each night if you don't see anything else you like! But.............I always splurge and enjoy the best dessert they have!! I guess you only live once

Hope this helps!