If you're like me, half a can is only half a meal, in which case it's necessary to double all the numbers on the Nutrition Facts panel, especially calories and sodium. Many Americans eat or drink more calories than they use and then pack on unwanted pounds. Based on a 2,000-calorie diet, meals should add up to approximately 600 calories, with one 200-calorie snack per day, according to Lanzano. A whole can of the lentil-vegetable soup I'm eyeing has 300 calories, so to make it a meal, Lanzano tells me I can add a bit more food — a slice of whole-grain bread or a piece of fruit.