Dietary fat is one of the most misunderstood concepts in human nutrition. Not all fats are bad.
Fats are most energy dense of all the macronutrients, at 9 calories per gram. Chemically, fats are made up of 3 elements: carbon, hydrogen, and oxygen. Saturated fats have a long carbon fatty-acid chain full of hydrogen ions. Unsaturated fats have double bonds that exist between carbon molecules. Trans fats are unsaturated vegetable oils that manufactures hydrogenate to make more solid so that they last longer. More than 90% of the fat in our body is triglycerides, which are 3 fatty acids stuck to a glycerol backbone. Cholesterol technically does not contain fatty acids, but it is classified as a lipid because it has some of the same chemical and physical characteristics as lipids.
What are the functions of fat? It is an energy source and provides thermal insulation that protects the vital organs from trauma. Fat serves as a vitamin carrier and hunger depressor. Fat is necessary for the production of many regulatory hormones; and for the production of structural components, such as brain development and function.
What is the difference between good and bad fat? In the typical American diet, saturated fat comes about 34% from plant sources and the rest from animal sources. It is recommended by health professionals to replace some of the saturated fat and all Trans fat with nonhydrogenated monounsaturated and polyunsaturated fats. Essential fatty acids are omega-3 fatty-acids, which are found in the oils of coldwater fish and flaxseed oil, and omega-6 fatty acids, which are found in meat, corn, oil, safflower oil, and sunflower oil. There are no firm dietary needs or standards for fat. The American Heart Association encourages people to focus on replacing high-fat foods with vegetables, fruit, poultry, lean meant, unrefined whole grains, and fat-free or low-fat dairy products. They recommend the omega-3 fatty acids in fish. It is also recommended that no more than 300 mg of cholesterol per day.
The American Cancer Society is more aggressive and encourages a diet that contains only 20 % of total calories from lipids to reduce the risk of certain types of cancer. A prudent recommendation is that 30% or less of your total calories should be from fat, and the majority should be unsaturated fat.
Let’s look at fat deficiencies and excesses. Inadequate absorption of fat may be due to steatorrhea, which can result in severe vitamin states. Very low-fat diet can be associated with gallstones.
• Are those butter substitutes like Smart Balance and Benecol, good for us?
• Are there any health risks associated with omega-3 fatty acids?
• What hidden fats do you sometimes eat?
• Why must we be concerned not just about the total amount of fats we eat we but also about those the types of fats?
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