One medium banana is two points under the "old" Weight Watchers point system. Under the PointsPlus system, a small or medium banana counts for zero points.
Weight Watchers converted its diet program to the PointsPlus system in 2010. The main difference between the old and new systems is that the new is based on fiber, fat, carbohydrates and protein, whereas the old system was based on fiber, fat and calories. The system was further adjusted in 2012 to include protein, fiber, fat and carbohydrates in its calculations. Notably, under the new points system, most fruits are zero points, including apples, mangoes, oranges, pears, peaches and watermelons.