If you are not going to have the protein and veg 'real food' meal for your fourth meal of the day you would need to have 4 packs. The calorie content of four packs on this programme is about the same as 3 on the others. Slightly smaller meals and only 1/4 of the nutrients you need rather than a third. It means you get to eat a less, a little more often. The meals are much tastier on S&S, so eating all four is more pleasant.