All fats are not equal. There are various kinds of fat and the human body processed them in different ways. There are commonalities, however. For example, every type of fat provides nine calories of energy per gram. Both carbohydrates and protein provide a lower amount -- four calories per gram – so fat is actually a more efficient energy source. Many nutrition experts suggest people should get 30 percent of their calories from fat each day.

Apart from the energy gats provide, they have distinct differences. Fats are classified as saturated, polyunsaturated, and monounsaturated.

Saturated fat

Saturated fats have been associated with increasing the amount of LDL (low density lipoprotein) cholesterol in the bloodstream. In turn, elevated LDL cholesterol is associated with increase risk of heart disease. Saturated fats are found in many foods from animal products like red meat, eggs, butter and other dairy products. A few vegetable oils also contain saturated fats including palm oil and coconut oil.

Polyunsaturated fat

Polyunsaturated fats are a better choice than saturated fats. However, they have downsides as well. Polyunsaturated fats have been shown to lower LDL cholesterol levels, which is a positive effect. However, it also may lower the HDL (high density lipoprotein) cholesterol, which is the "good" cholesterol in the body. Presence of a high level of HDL cholesterol can decrease the risk of heart attack, since it helps carry the LDL cholesterol away from the heart. Polyunsaturated fats are generally found in plant-based foods such as corn, safflower, sesame and sunflower oils. You will also find polyunsaturated fats in some seeds and nuts.

Monounsaturated fat

Monounsaturated fats are the best fats for our health. They help lower the LDL cholesterol, but they do not lower the HDL cholesterol. In fact, they may even raise HDL cholesterol levels. While it is important to eat only moderate amounts of fat, the fats that people consume should come primarily from monounsaturated sources. Several plants produce foods containing monounsaturated fats including olives and avocados. They are also found in almonds and hazelnuts. For this reason, many medical professionals recommend that people use extra virgin olive oil (the best olive oil) for all cooking and baking.

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