The phrase "calorie buck" refers to the value you get in terms of calories from the food you eat. It signifies the amount of energy you gain from consuming a particular food item. Full definition
While standard pasta doesn't offer much nutritional bang for its calorie buck, this versatile squash packs incredible amounts of vitamin A, vitamin C, beta carotene, lutein, folate and potassium. (blog.paleohacks.com)
The correction: Base meals and snacks on whole foods, which are less energy dense (translation: more filling bang for your calorie buck). (womenshealthandfitness.com.au)
So if you're trying to cut the calories and get the most protein bang for your calorie buck, tuna in water is the way to go. (tctmed.com)