Fats

Fats, and oils, are composed of molecules called fatty acids. Within these fatty acids, there are carbon atoms that are either linked by a single or double bond. If there are no double bonds between the carbon atoms in the fatty acid, then that fat is a saturated fat. If somewhere within the acid it does contain a double bond, then it is unsaturated. Monounsaturated fatty acids contain a single double bond; where as polyunsaturated fatty acids contain two or more double bonds.

Fats are 75% of the energy demand during extended aerobic work in an endurance-trained athlete. There is evidence that the rate of fat metabolism may be accelerated by consumption of caffeine before, and during, long activities. However, it's possible that insomnia, restlessness, and ringing in the ears can also occur. During moderate exercise, 1/2 of the total energy expended is from free fatty acid metabolism. If the moderate exercise exceeds an hour, the body uses mostly fats for energy. Using fat as fuel depends on how long the event is, and the athlete's condition. Trained athletes use fat for energy faster than untrained athletes. Runners should have a diet low in fat. Only 20-25% of total calories should be from fat.

Unsaturated fats, such as monounsaturated, are considered the "good" fats. Monounsaturated fats help maintain a high level of HDL cholesterol (good cholesterol), while lowering your LDL levels (bad cholesterols). Polyunsaturated fats are also good fats, and help the same way as monounsaturated fats. Unsaturated fats also ease inflammation and stabilize heart rhythms. Some examples of unsaturated fats are: almonds, hazelnuts, pecans, pumpkin seeds, walnuts, flax seeds, sunflower oil, corn oil, soybean oil, and flaxseed oil. Omega 3 fats are a type of polyunsaturated fats. Omega 3 fats are found in fish, such as salmon.

Saturated fat are the "bad" fats. Trans fats are harmful to teen bodies, and everybody, because it lowers the good cholesterol levels, and raises the level of bad cholesterols. If levels of bad cholesterols are too high, they can cause the person to have coronary heart disease. Trans fats are engineered by humans and are not a natural substance. Everybody is advised to consume as little trans fat products as possible, and if so, none at all. Saturated fats are mainly found in animal products, such as meat and whole milk diary products. Saturated fats raise the bad cholesterol levels as well as the good cholesterols. Like trans fats, everyone is advised to keep saturated intake levels as low as possible, 7% or lower is considered a good target. Some examples of saturated fats are: ice cream, cheese, red meat, half and half, butter, fatty beef, lamb, pork, poultry with skin, beef fat (tallow), and lard.



unsaturated fats
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