Lipids, oils and fats

 

The types of lipids

Lipids are formed of carbon, hydrogen and oxygen atoms. There are two types of lipids:

 

• Oils (which are liquid at room temperature).
• Fats (which are solid at room temperature).

 

Examples of foods which contain lipids:

 

Fats	Oils
Beef Lamb Chicken Oily fish Butter Milk Eggs Cheese	Olive oil Corn oil Sunflower oil Rapeseed oil Margarine Seeds Nuts Fish

 

 

How the body uses lipids

Lipids are the building blocks of cell membranes and some hormones in your body. For example, cholesterol is a lipid that makes sex hormones. Lipids also store energy as fat and insulate your body and organs.

You need lipids in your diet for good health. Lipids can be broken down into fatty acids and glycerol, which are important molecules for your body. Some fatty acids are essential and you can get them from foods like nuts, seeds or fish.

However, you should not eat too much food that is high in lipids. This is because lipids have a lot of energy and can make you gain weight if you do not exercise enough. The recommended amount of fat for adults and teenagers is no more than 70 g per day.

 

 

🍔 Knowledge Check: Lipids, Fats & Oils

Think you know your saturated from your unsaturated? Test your lipid knowledge below!

1. Which two molecules are the building blocks of a lipid?

• Glucose and Starch
• Amino Acids and Glycerol
• Fatty Acids and Glycerol

2. Which of the following is a key role of lipids in mammals?

• Thermal insulation to maintain body temperature
• Carrying oxygen in the blood
• Speeding up chemical reactions

3. In the Ethanol Emulsion test, what indicates a positive result for fat?

• The solution turns blue-black
• A cloudy white emulsion forms
• The solution turns brick-red

4. Compared to carbohydrates, lipids provide:

• Less energy per gram
• The exact same amount of energy
• More than double the energy per gram

Check Your Answers

1. Fatty Acids and Glycerol (Usually 3 fatty acids to 1 glycerol).
2. Thermal insulation (Fat layers under the skin reduce heat loss).
3. A cloudy white emulsion forms (Lipids don't dissolve in water, so they hang in droplets).
4. More than double the energy (Lipids are very energy-dense molecules).

 

Summary:

 

• Fats and oils are both types of lipids. Fats are solid at room temperature, while oils are liquid. Lipids play a vital role in a healthy diet. They provide energy, insulation and cell membrane components for the body.
• Lipids are a category of fats and oils. They have different physical states at room temperature: fats are solid and oils are liquid. Lipids are essential for a healthy diet. They store energy, insulate the body and form cell membranes.