Dietary Fats: Types and Their Role in Disease

Our bodies require a certain amount of dietary fats for survival. The balance lies in choosing the correct fats for optimal health and nutrition.

Fats, or lipids, are a class of macronutrients that are essential for human nutrition. The most common food sources of fats are meats, dairy, nuts, and seeds; although fat can be found in most food. Since fat is necessary for survival, at least a minimum amount must be consumed in the diet. Excessive intake of fats though, can lead to many health problems, such as obesity, cardiovascular disease, diabetes, and some cancers.
The Role of Fats in the Body

Every cell and organ in the human body requires fats to function properly. They keep cells strong, help maintain the nervous system, aid in manufacturing some hormones, and support the health of the brain, blood, liver, and skin. Fats also serve as a ready energy source, providing 9 calories per every gram. Any stored fat can be used as energy in times of reduced food intake. Fats will also provide cushioning to internal organs, protecting them from trauma and extreme cold. Some vitamins are dependant on fats to be able to be absorbed in the body.

Types of Fats – Saturated, Monounsaturated, and Polyunsaturated

For optimal health and nutrition, our bodies need both saturated and unsaturated fat. Although they should be kept to a minimum, saturated fats are helpful in the body; they stabilize cell membranes and are not very susceptible to damage. The main food sources of saturated fat are meat and dairy. Processed foods also contain saturated fat. Some vegetable oils can also be saturated. Coconut oil is a unique form of saturated fat that provides several health benefits.

Monounsaturated fats are mostly found in oils, nuts, and avocados. When consumed in moderation these fats help to lower the bad cholesterol, LDL, and have little to no effect on good cholesterol, or HDL. Research is also showing that consumption of monounsaturated fats leads to improved cardiovascular health.

Polyunsaturated fats are derived from vegetable sources, such as sunflower, sesame, soybean, corn, and safflower oil. They also affect cholesterol levels; however these fats have been shown to lower both bad cholesterol levels, and good cholesterol levels. Consumption of polyunsaturated fats should be kept to a minimum. The exception to this rule is omega-3 and omega-6 fatty acids. These essential fatty acids (EFA’s) are not produced in the body, and must be obtained through diet. Good sources of omega-3 fatty acids are the seeds and oils of flax, chia, and pumpkin, and some coldwater fish. Omega-6 fatty acids are found in most plant oils, wheat germ, and rice bran.

Dietary Fats and Disease

While consuming fat in the diet is essential, both the amount of fat and the type of fat consumed must be considered. Too much saturated animal fat, trans fat, and hydrogenated fat in the diet is linked to increased risk of disease. Cardiovascular disease, including atherosclerosis, high cholesterol, heart disease, and high blood pressure, are all related to increased fat intake. Two types of cancer, colon and breast, are also associated with a high-fat diet. Eliminating trans fat and hydrogenated fat, and reducing animal fats, combined with increasing EFA’s, fiber, and vegetables, is a good start to improving overall health.
Read on

* Lower Cholesterol and Maintain Good Heart Health
* Trans Fatty Acids - the Fats That Must be Avoided
* The Skinny on Dietary Fats

Consuming the correct types of fat, while avoiding the bad fats, is an essential step in achieving optimum nutrition and health.

Sources:

Haas, Elson, MD., Staying Healthy With Nutrition. California: Celestial Arts, 2006.

Shulman, Joey., Winning the Food Fight. Mississauga: Wiley, 2003.

First published Jul 31, 2010 Lisa Frizzo