The fat in your body is divided into two categories: body fat and dietary fat. Body fat is the fat you store under your skin, between the muscle fibers and around your organs. Dietary fat is the fat you get from the foods you eat. Dietary fat has three distinct types: saturated, unsaturated and trans fats. How fat affects your body depends on the category and type of fat.
Body Fat
Body fat is the result of excess calories in your diet, including dietary fat. Your body uses this fat primarily for energy but it also uses it for insulation and shock absorption, especially around your organs. Your body also needs a bare minimum, or essential, amount of body fat to regulate hormone production, including sex hormones. Normal body fat ranges vary by age and gender, but the average range is 21 to 30 percent for women and eight to 24 percent for men. Having too much body fat can be detrimental to your health, as your cardiovascular system has to work harder to carry the excess weight around. Excess body fat may also make you more susceptible to diseases such as diabetes, hypertension and heart disease. Too little body fat is also damaging because your body is not able to maintain vital processes.
Unsaturated Fats
Unsaturated fats are liquid at room temperature and come from both animal and plant resources. Unsaturated fats are characterized by the types of chemical bonds they have. Monounsaturated fats have one double carbon bond while polyunsaturated fats have more than one. Monounsaturated fats improve your blood cholesterol levels and polyunsaturated fats promote heart health and may decrease the risk of type 3 diabetes, according to the Mayo Clinic. Although these fats are considered beneficial, too much of either type of fat can contribute to obesity. Foods with monounsaturated fats include olives, avocados, nuts and their oils. Foods with polyunsaturated fats include fish, fish oil and soybean, sunflower, sesame and corn oils.
Saturated Fats
Saturated fats are solid at room temperature and come primarily from animal sources, with a few plant sources. Unlike the unsaturated variety, saturated fats have been linked with high cholesterol and coronary artery disease. Excess saturated fats can also contribute to obesity. Animal sources of saturated fat include red meat, including beef, pork and lamb; poultry such as chicken and duck; and dairy products. Plant sources of saturated fat include cocoa butter, coconut oil and palm oil, which are often used in processed foods.
Trans Fats
Trans fats are unsaturated fats that have been altered by adding hydrogen ions to the fat to remain solid at room temperature. Trans fats may increase you levels of "bad" low-density lipoprotein, or LDL, cholesterol and decrease your levels of beneficial high-density lipoprotein, or HDL, cholesterol. Your total blood cholesterol should be below 200 mg/dL -- an HDL higher than 60 mg/dL and an LDL lower than 129 mg/dL are ideal. If your LDL is higher, or your HDL is lower than ideal, you are at greater risk for hypertension and stroke. Trans fats are usually found in processed foods such as margarines and baked goods.
References
- "Principles of Anatomy and Physiology"; Gerard J. Tortora et al.; 2010
- Mayo Clinic: Dietary Fats: Know Which Types to Choose
Member Comments