modert

To be honest, when it comes to weight loss and the burning of calories all fat is the same. One fat over another will not increase your chances of weight loss. All oils, regardless of if they are saturated, polyunsaturated, or monounsaturated, have approximately 120 calories per tablespoon, and neither will directly improve your metabolic function.

Ubernier's reply is exactly correct - but I will expand on the polyunsaturated fats a bit. PUSF's are either Omega-6 or Omega-3 essential fatty acids. The desired ratio in a healthy diet is 2:1, meaning for every 2 grams of an Omega-6 you should consume 1 gram of an Omega-3. The problem is that the average american diet has a ratio of about 20:1 This is mostly due to all the vegetable oils (corn oil, cottonseed oil, safflower oil, etc) used in common cooking oils and margerines. Studies show that when you overconsume the Omega-6 fats and underconsume the Omega-3 fats, you have an increased risk of a variety of illnesses, including heart disease, skin conditions, and arthritis! People would greatly benefit by shifting the ratios back to 2:1 and this can be accomplished by choosing the right foods.