A class 2 lever has the load between the fulcrum and the effort. Because the load and effort are on the same side, they move in the same direction. In a class 2 lever, the load is always closer to the fulcrum than the effort, so class 2 levers are used to make it easier to move the load.
It cause weight loss because the diets make you avoid certain food that have higher amount of some thing’s such as carbs or fat in them. If you avoid less of something then you will overall be getting less it therefore you will lose weight