1. Protein A macronutrient

2. Protein facts
Eating one gram of protein provides the body with 17 kilojoules of energy
Protein is especially important during times of growth, such as during adolescence and pregnancy

3. Protein facts Many amino acids join together to make protein.
Protein is broken down into amino acids during digestion for easy absorption
Some are stored in the liver to make new proteins and tissues required by the body

4. Structure of protein
Protein is made up of amino acids (AAs); there are 2 types of AAs:
Essential cannot be made by the body (must be taken in food)
Non-essential can be made by
the body

5. Functions of protein
The nitrogen in protein helps with growth and repair and maintenance all body tissues (e.g. skin, nails, muscle).
Hormones, enzymes and antibodies are made and regulated from protein

6. Functions of protein
Protein regulates body processes such as water balance both inside and outside cells
Provides structure to the body e.g. collagen is the strong and flexible framework for skeleton, tendons, connective tissue
Protein provides some energy if supplies from CHO and fats are low

7. Food sources There are two types of protein sources: Complete proteins
Foods that contain all of the essential AAs
e.g. meat, fish, cheese, soy beans and milk from animal sources
Incomplete proteins
Food that does not contain all of the essential AAs
e.g. vegetables, grains and nuts

8. Food sources Meat, fish, poultry Whole milk Eggs Cheese Soya beans
Are complete proteins – contain essential amino acids

9. What about vegetarians?
Eating foods in combination can allow this complete protein to be available, e.g. baked beans on wholemeal toast