Fat is the body's major form of stored energy. One gram of fat provides 9 calories. That's more than twice as many as carbohydrate or protein

There are two main types of fat: saturated and unsaturated.
When you eat fat, you'll get both of them. All fat provides the same calories, but unsaturated fat (which includes polyunsaturated fat and monounsaturated fat) is best for health.
Polyunsaturated fat includes omega-3 fat; you'll find it in fish and soy foods. Omega-3's are healthy, so enjoy two or more good omega-3 sources each week.
Monounsaturated fat is in olives, avocados and peanuts. Both of these fats are healthy.

Saturated fat comes from animal foods (like high-fat meat, dairy and chicken skin), tropical oils (like coconut and palm) and lard.
Unsaturated fat mainly comes from plants and fish. High sources include olive, vegetable and canola oils.