Explain why a balanced diet is important for the healthy functioning of the human body.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
A balanced diet contains the correct amounts of carbohydrates, proteins, fats, vitamins, minerals, fibre, and water. Without a balanced diet, a person may develop a deficiency disease or suffer from malnutrition.
Model answer (4 marks)
Carbohydrates and fats supply the energy required for metabolic processes and respiration, allowing cells to function.
Proteins are essential for the growth and repair of cells and tissues, providing the building blocks for body structures.
Vitamins and minerals prevent deficiency diseases by acting as co‑enzymes or structural components in biochemical reactions.
Fibre helps food move through the digestive tract, preventing constipation, while water is required for all chemical reactions and for the transport of nutrients and waste products.
Proteins are essential for the growth and repair of cells and tissues, providing the building blocks for body structures.
Vitamins and minerals prevent deficiency diseases by acting as co‑enzymes or structural components in biochemical reactions.
Fibre helps food move through the digestive tract, preventing constipation, while water is required for all chemical reactions and for the transport of nutrients and waste products.
Examiner tips
- Use the exact terms from the mark scheme (energy, growth, repair, deficiency diseases, transport).
- Show the link between each nutrient and a specific bodily function.
- Keep each point brief – one sentence per point.
Common mistakes
- Confusing fibre with protein or fat.
- Forgetting to mention water’s role in transport and reactions.
Mark scheme (4 marks)
- Carbohydrates and/or fats are needed to provide energy (for metabolic processes / respiration).
- Proteins are needed for growth and repair of cells/tissues.
- Vitamins and/or minerals are needed to prevent deficiency diseases.
- Fibre is needed to aid the movement of food through the digestive system / prevent constipation; water is needed for chemical reactions / transport in the body.
Key terms in this question
Related
- All Eduqas GCSE Biology revision notes →
- How to answer a "Explain" question →
- Decode the mark scheme abbreviations →
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