What two roles do fats play in the body?

While carbohydrates are the main source of fuel in your body, your system turns to fat as a backup energy source when carbohydrates are not available. Fat is a concentrated source of energy. One gram of fat has 9 calories, which is more than double the amount of calories from carbohydrates and protein. Some types of vitamins rely on fat for absorption and storage. Vitamins A, D, E and K, called fat-soluble vitamins, cannot function without adequate daily fat intake. These vitamins are essential parts of your daily diet. Vitamin A keeps your eyes healthy and promotes good vision, vitamin D assists in keeping your bones strong by boosting calcium absorption, vitamin E protects cells by neutralizing free radicals and vitamin K is important for blood clotting. If you don't meet your daily fat intake or follow a low-fat diet, absorption of these vitamins may be limited resulting in impaired functioning.

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