Who this is for: Cambridge IGCSE Biology (0610) students who want diet — the seven food groups, their sources and deficiency diseases — to become a reliable source of marks instead of vague “eat healthy” answers.
What query it owns: how to understand and revise diet in Cambridge IGCSE Biology (0610).
Why this is safe: this page owns the diet revision-guide angle, while Tutopiya’s Diet subtopic page owns the learning resource and the free Diet quiz owns the practice.

Diet is the entry point to Human Nutrition in Cambridge IGCSE Biology (0610). Whenever a question involves food groups, sources of nutrients, balanced diets or deficiency diseases such as scurvy and rickets, examiners expect precise links between nutrient, function and symptom. This guide explains exactly what diet covers, how to handle the question types that actually appear, and where to practise each skill.

Key takeaways

• A balanced diet contains the right proportions of carbohydrates, proteins, fats, vitamins, minerals, fibre and water.
• Carbohydrates and fats provide energy; proteins for growth and repair; fibre for peristalsis.
• Key deficiencies: vitamin C → scurvy; vitamin D → rickets; iron → anaemia; calcium → weak bones/teeth.
• Obesity results from energy intake exceeding energy used over time.

What is diet in Cambridge IGCSE Biology?

Diet refers to the food a person eats. A balanced diet provides all nutrients in the correct proportions for health, growth and activity. Carbohydrates and fats are energy sources; proteins provide amino acids for growth and repair; vitamins and minerals are needed in small amounts for specific functions; fibre aids movement of food through the gut; water is essential for chemical reactions and transport.

Read the full explanation on Tutopiya’s Diet subtopic page before attempting questions.

The core ideas you must master

Nutrient	Main function	Source examples	Deficiency
Carbohydrates	Energy	Bread, rice, pasta	Low energy
Proteins	Growth, repair, enzymes	Meat, fish, beans	Poor growth
Fats	Energy, insulation	Oil, butter, nuts	—
Vitamin C	Connective tissue, immunity	Citrus fruits	Scurvy
Vitamin D	Calcium absorption, bones	Sunlight, oily fish	Rickets
Iron	Haemoglobin	Red meat, spinach	Anaemia
Calcium	Bones, teeth	Milk, cheese	Weak bones
Fibre	Peristalsis	Whole grains, vegetables	Constipation

How to answer diet questions — step by step

1. Identify the nutrient the question names or implies.
2. State its function — energy, growth, specific body role.
3. Give a food source — at least one syllabus-appropriate example.
4. For deficiency questions — nutrient missing → disease/symptom chain.
5. For balanced-diet questions — list all seven components with proportions idea.
6. For obesity questions — energy in > energy used → fat stored.

Test yourself with the free Diet quiz.

Diet in past-paper wording: command words that matter

Command word / phrase	What the question wants	Typical diet stem
State	Short fact	”State one source of vitamin C.”
Define	Precise meaning	”Define a balanced diet.”
Describe	What happens	”Describe the symptoms of scurvy.”
Explain	Reason or link	”Explain how lack of iron causes anaemia.”
Suggest	Apply to context	”Suggest why this diet is unbalanced.”

Worked exam-style stems (how to answer the wording)

1. “Define a balanced diet.” A diet containing all the main nutrients in the correct proportions for health, growth and activity. Reward: all nutrients + correct proportions.

2. “Describe the symptoms of scurvy.” Bleeding gums, wounds fail to heal, weakness — caused by lack of vitamin C. Reward: symptoms + vitamin C named.

3. “Explain why a person who eats more energy than they use may become obese.” Excess carbohydrate and fat converted to stored fat → body mass increases → obesity. Reward: energy balance concept.

Diet scenarios in past-paper wording: table completion stems

Many diet questions present a meal or weekly menu and ask you to identify what is missing. Use this decision flow.

Observation in the stem	Likely missing nutrient	Disease / symptom to name
Child with bowed legs, little sunlight	Vitamin D (or calcium)	Rickets
Tired person, pale skin, low red meat intake	Iron	Anaemia
Sailor with bleeding gums, no fresh fruit	Vitamin C	Scurvy
Diet high in sugar and fat, sedentary lifestyle	Energy balance issue	Obesity risk

4. “A child eats mostly bread and rice but no meat, beans or fish. Suggest one nutrient that may be lacking and describe a symptom.” Protein — poor growth, slow repair of tissues, weakness. Reward: nutrient named + growth/repair symptom linked.

Diet links forward to Digestive System, Physical Digestion and Chemical Digestion. The Cambridge IGCSE Biology resource hub links every Human Nutrition resource.

Common mistakes students make

• Listing food names without naming the nutrient group.
• Confusing vitamin D deficiency (rickets) with calcium deficiency (weak bones).
• Saying fibre provides energy — it aids peristalsis.
• Omitting water from balanced-diet lists.
• Describing scurvy without naming vitamin C.

When you need more support

If deficiency-disease questions keep costing marks, work through the Diet quiz, then book a Cambridge IGCSE Biology tutor.

Frequently asked questions

How many food groups must I know? Seven — carbohydrates, proteins, fats, vitamins, minerals, fibre and water.

Which deficiency diseases are essential? Scurvy (vitamin C), rickets (vitamin D), anaemia (iron) — know symptoms and causes.

Is diet tested with digestion? Yes — diet sets up what the digestive system breaks down and absorbs.

How do I revise diet effectively? Read the subtopic notes, practise state and explain stems, then take the Diet quiz.

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