Fats

Fat

Fat has many vital functions in the body which include:

• Energy - fat provides up to 70% of total energy at a resting state

• Nerves - fat is a component of nerve fibers and cell membranes

• Protection - fat cushions and supports vital organs

• Hormones - fat helps to produce certain hormones in the body

• Storage and transportation - fat stores and transports fat-soluble vitamins

• Insulation - fat preserves body heat

The USDA recommends that adults consume no more than 29% of their total daily calories from sources of fat (this percentage varies for other population groups so reference the previously listed recommendations). Diets that are very low in fat (less than 20% of total calories consumed per day) can decrease the vital functions that fat serves in the body. Diets that are very high in fat (over 30% of total calories consumed per day) are associated with a number of diseases including hyperlipidemia, atherosclerosis, certain types of cancer, type 2 diabetes, as well as obesity and the associated risks of obesity.
Sources of Fat
The proportion of fat intake should be derived from the following:
Saturated/Trans Fats: <10%
Polyunsaturated: ~10%
Monounsaturated: ~10%
Healthier Fats (Unsaturated fats)
When choosing fat sources, it is recommended that individuals primarily consume unsaturated fats, such as monounsaturated and polyunsaturated fats (see chart below).  These fats can aid in lowering the risk of certain chronic diseases, such as heart disease.  Total cholesterol and low-density lipoprotein (LDL) cholesterol ("bad" cholesterol), can be reduced by consuming unsaturated fat.
It has been found that polyunsaturated and omega-3 fatty acids in particular may be especially beneficial to your heart. Omega-3 fatty acid consumption has been associated with a decrease in the risk of coronary artery disease, protection against irregular heartbeats, and may help lower blood pressure levels (8, 24).
Food Sources of Healthier Fats
Healthier Fats Food Source
Monounsaturated Olive oil, peanut oil, canola oil, avocados, nuts and seeds
Polyunsaturated fat Vegetable oils (such as safflower, corn, sunflower, soy and cottonseed oils), nuts and seeds
Omega-3 fatty acids Fatty, cold-water fish (such as salmon, mackerel and herring), flaxseeds, flax oil and walnuts

Adapted from:  Mayo Foundation for Medical Education and Research (MFMER).  www.mayoclinic.com.  2010.

Less Healthy Fats (Saturated Fats)

Less than ten percent of consumed fats should come from saturated fat, as this is the least healthy type of fat. Excessive consumption of saturated fat has been associated with and increase of certain chronic diseases - namely heart disease.  Elevated levels of LDL ("bad" cholesterol) have been shown to increase from diets high in saturated fat. Excessive intake of "trans fat" has also been associated with an increase in blood cholesterol levels and should, therefore, be consumed at less than ten percent of total fat intake.

Food Sources of Less Healthy Fats

Saturated fat Animal products (such as meat, poultry, seafood, eggs, dairy products, lard and butter), and coconut, palm and other tropical oils
Trans fat Partially hydrogenated vegetable oils, commercial baked goods (such as crackers, cookies and cakes), fried foods (such as doughnuts and french fries), shortening and margarine

Adapted from:  Mayo Foundation for Medical Education and Research (MFMER).  www.mayoclinic.com.  2010.

For a detailed list of the fat content of various foods, please see Appendix A at the end of the course.