A balanced diet
A balanced diet
- A balanced diet gives all the substances you need, in the right amounts.
- There are seven parts.
- Missing a vitamin causes a deficiency disease.
The seven parts
| Part | Why you need it |
|---|---|
| carbohydrates | main source of energy |
| fats | energy store; keep you warm |
| proteins | growth and repair |
| vitamins (C, D) | C: healthy skin/gums; D: take in calcium |
| minerals | calcium → bones/teeth; iron → red blood cells |
| fibre | keeps food moving through the gut |
| water | needed for all reactions |
Practice
Proteins are needed mainly for:
Protein is used for growth and repair; carbohydrates and fats are the main energy sources.
Practice
Iron is needed to make:
Iron is needed for red blood cells; calcium is for bones and teeth.
Deficiency diseases
- too little vitamin C → scurvy (bleeding gums).
- too little vitamin D → rickets (soft, bent bones).
Practice
A lack of vitamin C causes:
Too little vitamin C causes scurvy; too little vitamin D causes rickets.
Practice
Rickets (soft, bent bones) is caused by a lack of:
Vitamin D helps the body absorb calcium; without it, bones become soft (rickets).
You've got it
Key idea
- carbohydrates/fats = energy; protein = growth & repair; iron = red blood cells; calcium = bones/teeth
- fibre keeps food moving; water is needed for all reactions
- vitamin C deficiency → scurvy; vitamin D deficiency → rickets