The quantity of fat cells, once formed, remain with you throughout your natural life. Reducing your caloric intake will reduce or burn excessive fat, which means the fat cells become smaller. The control you have, through diet and exercise, is on the size of the fat cell, not the quantity.
The medical and nutritional advice that you receive, should recommend that you be concerned with your percentage of body fat, rather than the total body weight. The recommended ranges are 19% - 26% of body fat for women and 12% - 18% of body fat for men.