Fats are made up of the same elements as carbohydrates –carbon, hydrogen, and oxygen – but the way the atoms are linked together is different. Fats can be found in both plants and animals and are insoluble in water.
They are grouped in three categories:
a) Simple fats (triglycerides)
b) Compound fats (phospholipides, glucolipids, lipoproteins)
c) Derived fats (cholesterol)
Fats in the body serve three functions:
- They provide the major source of stored energy.
- They serve to cushion and protect the major organs.
- They act as an insulator, preserving body heat and protecting against excessive cold.
Fat is the most calorie-dense of any nutrients. A pound of fat contains 3500 calories, as opposed to 1600 calories stored in a pound of protein or carbohydrate.
When you exercise, assuming you stay within your aerobic capacity, the body uses fats and carbohydrates for energy on about a 50-50 basis. But the longer you continue to exercise, the higher percentage of fat used. After three hours or so, the body may derive as much as 80% of its energy from fat.
Fat molecules differ biochemically in their composition, being saturated, unsaturated or polyunsaturated. Diets high in saturated fat tend to raise the cholesterol level of the blood. Therefore, health experts recommend that something like two thirds of your fat intake by polyunsaturated fats.
Saturated fats are found in foods such as:
Buff
Lamb/Goat
Pork
Chicken
Shellfish
Egg Yolks
Cream
Milk
Cheese
Butter
Chocolate
Unsaturated fats are found in:
Avocadoes
Cashews
Olives and Olive oil
Peanuts, peanut oil, peanut butter
Polyunsaturated fats are found in:
Almonds
Sunflower oil
Corn oil
Soyabean oil
Walnuts, etc.