Sticking to a Diet While Dining Out is Nearly Impossible, Study Shows: University of Toronto researchers have found that among 19 sit-down restaurant chains, the average meal contained 1,128 calories, which is 56% of the average daily 2,000-calories intake that the Food and Drug Administration recommends for a healthy adult (interestingly enough, the average fast food meal contains 881 calories). The high calorie counts weren’t just found in dinner portions, either: Lunches packed more than 1,000 calories on average, and breakfasts weighed in around 1,226. So if you’re trying to cut calories and still eat out, ask for a doggie bag.