Diet and Digestion

Learning Objectives:

• To understand the main parts of the human diet.

Starter:

• What did you have to eat yesterday?

• Is what you have eaten good for you?

Why do we need a balanced diet?

Food provides us with the energy and materials required for: growth development repair reproduction

What is a balanced diet?

We need the right amounts of nutrients in balance to maintain good health and organ functions.

Food provides us with energy to: maintain healthy weight have a strong immune system be healthy enough to work and learn be happy

The Seven Food Groups

Carbohydrates

Water

Protein

Vitamins

Minerals

Fibre

Fats

Nutrient Role in Body Examples

Carbohydrates

Lipids

Proteins

Vitamins

Minerals

Fibre

Water

Carbohydrates

Carbohydrates give you energy. We usually talk about 2 types of

carbohydrates: simple - sugars complex - starch

Lipids (Fats)

Used to make cell membranes Stored to insulate organs - protection &

keeping warm Source of energy Essential for fat-soluble vitamins (A, D, E) Some make prostaglandins & hormones Long-chain omega-3 fatty acids in fish oils

protect us from heart disease

Proteins

Use to make enzymes, hormones, antibodies, haemoglobin, muscles, cells membranes, collagen and elastin in connective tissue, bone.

Used for growth and repair of tissues.

Vitamins

Summary video

VitaminsRole in Body Examples of Foods

B group - coenzymes, aid processes eg respiration

cereals, wholemeal bread, leafy greens

A - dim-light vision, epithelial tissue, immune system

liver, green veg, orange fruit & veg

C - helps make connective tissue & absorb Fe in food

citrus, blackcurrants, kiwi fruit, peppers, potatoes

D - helps absorb Ca & deposit it in bones, protects against cancer & heart disease

oily fish, eggs, liver, made in skin when exposed to sunlight.

A,C,E - antioxidants, protect DNA & against cancer & heart disease

E: nuts, wholemeal bread

MineralsRole in Body Examples of Foods

Fe - making haemoglobin red meat, spinach

Ca - hardens bones & teeth, helps blood clot, nerve conduction, muscle contraction

milk, cheese, yoghurt, broccoli

Na & K - nerve conduction & heart function

Na: table salt

K - bananas

P - make cell membranes & ATP for bones

cheese, pork, tuna, nuts

Mg - bones green veg

I - thyroxine table salt, seafood

Zn - insulin meat, cereals, nuts, milk

Fibre

Indigestible plant matter, such as cell walls - adds bulk to food and takes up water in the gut. Helps us pass faeces easily.

Soluble fibre helps lower blood cholesterol levels

Water

Makes up 70% of us - blood plasma is 90% water.

Needed for transport in the body. Needed for sweat, tears and urine.

Superfoods

Some foods have been described as super foods, they are rich in several nutrients

Suggest why super foods are good for you and what effects they may have?