HHD - SAC 3

Nutrients

• Substances that provide nourishment, essential for the maintenance of life and for growth.

  • When eating food is broken down in the process of digestion to release nutrients.

Two groups of Nutrients

• Macronutrients - required in high quantities

• Micronutrients - only needed in small quantities

6 different types of nutrients

• Water

• Vitamins

• Proteins

• Fats

• Minerals

• carbohydrates

Carbohydrates

• Function = to provide fuel to the body, it is the bodies preferred source of energy.

  • Carbohydrates are broken down into glucose molecules, which are then absorbed into the bloodstream and stored as glycogen.

Carbohydrates within food

• Found in foods of plant origin (wheat, corn, oat)

  • also found in sugar and foods containing sugars.

• Major food sources of carbohydrates: vegetables, bread, rice, pasta, cereals and fruit.

Fibre

• Type of carbohydrate, that does not get absorbed by the body and is required for optimal health and wellbeing.

  • etc - bran, wholemeal bread, grains and seeds, fruits and vegetables.

• Fibre benefits : feelings of fullness, reduces cholesterol, absorbs water, prevents constipation.

Protein

• Functions =

  • build, maintain and repair body cells

  • acts as fuel for producing energy

• Made up of amino acids, 20 different types of amino acids needed to function properly

  • 11 - non essential amino acids, synthesised in the body from other amino acids.

  • Other 9 - essential amino acids, cannot be synthesised in body and must be consumed.

Complete and Incomplete protein (type of essential amino acids)

• Complete = contains all essential amino acids

• Incomplete = does not contain all essential amino acids.

Fats (Lipids)

• Concentrated source of energy

• Function

  • act as fuel for energy

  • required for the development and maintenance of the cell membranes

  4 different types of fats:

• Monounsaturated

• Polyunsaturated

• Saturated

• Trans

Monounsaturated and polyunsaturated fats - “good fats”

Reduces Cholesterol, supports brain function and promotes heart and blood vessel health.

• Monounsaturated :

  • assists in lowering low density lipoproteins (LDL)

  • olive oil, canola oil, avocado, nuts

• Polyunsaturated:

  Omega 3 and Omega 6, lowers low density lipoproteins in the blood, and increases HDL (good cholesterol)

  • Omega 3 - fish

  • Omega 6 - mainly nuts

Saturated and Trans fats - “Bad fats”

• Saturated fats:

  • generally found in foods of animal origin

  • etc. full cream milk, cream, cheese, baked goods

• Trans fats :

  • created when liquid oil is converted into solid fat through a process called hydrogenation.

  • etc. found in processed foods - pies, pastries, cakes and margarine.

Water and Role

• makes up 50-75% of the body

• forms the basis of blood, digestive juices, urine and perspiration.

• contained in lean muscle, fat and bone

  • amount of water needed depends on body size, metabolism, weather, activity levels and food we eat

• Role:

  • medium for all chemical reactions required to provide energy

  • key component of cells, tissues, blood and systems.

Water sources and benefits

• water in its purest form is the bodies preferred source of hydration

• Benefits

  • weight management, reduces risk of obesity, cardiovascular disease and type 2 diabetes.

• Food sources

  • Watermelon, apple, Pineapple, celery and cucumber

Calcium

• Required for the building of bone and other hard tissues (e.g teeth and cartilage), therefore important during time of rapid growth to increase bone density

• Oxalic acid- found in food sources, prevents all of the calcium from being absorbed.

  • dairy products, sardines, green leafy vegetables, fortified soy milk.

Sodium

• Important mineral for the body

• regulates fluids from the body such as water and blood

  • table salt, olives, meat, cheese, processed foods.

• Over consumption of sodium

  • draws excessive fluid out of cells (increases blood volume)

  • stroke, heart attack, heart failure

  • kidney disease

  • osteoporosis

Iron

• As blood volume increases during youth, iron is needed in greater quantities.

• Iron is an essential component of haemoglobin (oxygen carrying component of the blood), and helps to produce red blood cells.

• Not enough Iron - can lead to conditions such as anaemia (tiredness/ weakness)

  • lean red meat, leafy green vegetables such as kale, oily fish, nuts.