What is the difference between saturated and unsaturated fat?

Fats are molecules made of carbon, hydrogen and oxygen. The type of fat depends upon the arrangement of these atoms within the molecule. If the carbon atoms have a single bond between them and as many hydrogen atoms as possible are bonded to the carbon atoms, then the fat is said to be saturated.

Sometimes though, the bond between the carbon atoms is a double bond and the molecule can absorb more hydrogen atoms. If this is the case, the fat molecule is of the unsaturated type of fat.

In a healthy diet, people usually want to limit or avoid the saturated fat. Saturated fat is known to raise blood cholesterol levels. Saturated fat is found in foods such as fatty meats, poultry skin, coconut and palm oils, pastries, cookies and high fat dairy products like whole milk.

Some fat is needed in a regular healthy diet. Fats are a potent source of energy for the body. Also, fat is needed to dissolve certain vitamins that our cells require. If there isn't any fat in the diet then the person will not be able to see the benefits of vitamin A, D, E and K. These vitamins will only dissolve in fat. The fat in a person's diet allows these vitamins to dissolve and then the vitamins can be carried to the cells within the person's body.

Unsaturated fats are divided into two groups:

• polyunsaturated fat: is found in fatty fish like salmon, tuna and sardines, and in oils like corn oil, safflower oil and soybean oil.
• monounsaturated fat: is found in some nuts (peanuts, almonds, hazelnuts, and pecans) as well as in certain oils like canola oil, and olive oil.

Activity

Reading:

Read the information found at one or all of these sites. After reading you want to be able to tell someone about the difference between a saturated fat and an unsaturated fat as well as knowing various foods that contain saturated fat and unsaturated fat.

• site a
• site b
• site c
• site d
• site e
• site f
• site g
• site h

Writing:

In your notebook explain the difference between unsaturated and saturated fats. Then give three examples of foods that contain each type of fat.

Sharing:

Talk with a classmate (either one in the room with you or one on line). Explain to each other the difference between unsaturated and saturated fats. Compare your examples of foods that contain saturated fat and then compare your examples of food that contain unsaturated fat. If you and your classmate disagree then contact your teacher for clarification.

Assignment

Do the attached assignment. Classify the fat in each of these foods as either saturated or unsaturated.

Remember there are two types of fat: saturated and unsaturated. Also the saturated fats can be further classified as monounsaturated fats and polyunsaturated fats.

Read the lesson material again if you still feel uncertain about classifying the fats in foods.

Example question:

Classify the fat contained in these foods:

a. whole milk saturated

b. theater popped popcorn saturated

c. salmon unsaturated (polyunsaturated)

d. peanuts unsaturated (monounsaturated)

When ready, click here for your questions.

Assessment

You will be tested on the difference between saturated and unsaturated fats on your unit test. Be sure that you can explain the difference between them and that you can identify sources of both types of fats.