Caloric dilution occurs when you combine a food of higher caloric density with a food of lower caloric density, thus diluting the overall caloric content of the plate/meal, and theoretically, your overall intake of calories.
For instance, if you take a food of medium caloric density, like a sweet potatoes (408 calories per pound), and eat it with a low calorie food, like romaine lettuce (77 calories per pound), with half the plate filled with each, you’ve diluted the calories of the sweet potato to something lower. Studies have shown that if you fill up your stomach with high nutrient, water rich, low calorie foods, you’ll eat fewer calories overall at the meal, even if you’re including some amount of higher-calorie food. When eating low fat whole vegan foods in unlimited quantities isn’t leading to weight loss, many nutrition experts suggest greater emphasis on caloric dilution. This approach often bears fruit, but frequently caloric tracking is necessary if you’re only a few pounds overweight.