There are two main types of unsaturated fat -- monounsaturated fats and polyunsaturated fats. While monounsaturated fats can modestly lower LDL cholesterol, polyunsaturated fats can lower LDL cholesterol and raise HDL cholesterol levels. Some forms of polyunsaturated fats, like omega-3 fatty acids, can also lower your triglycerides.
The National Cholesterol Education Program recommends that your consumption of monounsaturated fats be no more than 20% of your normal daily caloric intake, whereas your polyunsaturated fat intake should be no more than 10% of your daily intake. If you want to begin including unsaturated fats in your diet, make sure that these foods replace other fatty foods that are already in your diet, rather than add to them. Otherwise, you may risk gaining weight and increasing your cholesterol levels.
The following foods are high in monounsaturated fats:
- peanut butter
- olives
- nuts almonds, pecans, pistachios, cashews
- avocado
- seeds sesame
- oils olive, sesame, peanut, canola
- walnuts
- seeds pumpkin, sunflower
- flaxseed
- fish salmon, tuna, mackerel
- oils safflower, soybean, corn
Sources:
Rolfes SR, Whitney E. Understanding Nutrition, 3rd ed 2005.
Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (PDF), July 2004, The National Institutes of Heath: The National Heart, Lung, and Blood Institute.

