# A student is investigating the relationship between diet and health. Explain how an unbalanced diet can lead to health problems, referring to the roles of carbohydrates, proteins, lipids, and vitamins or minerals in the body.

> OCR A-Level Biology B — Advancing Biology (H422) — 2.3 Diet, nutrition and health · Explain · 5 marks

> A school nurse records that several students in Year 10 are consuming diets that are either too high in certain nutrients or lacking in others. Some students show signs of weight gain, while others appear to have stunted growth or signs of deficiency diseases.

## Mark scheme (5 marks)

1. Carbohydrates (and/or lipids) provide energy, and excess intake leads to obesity / weight gain
2. Proteins are needed for growth and repair of cells/tissues, and a lack of protein leads to poor growth or muscle wasting
3. Vitamins and/or minerals are needed in small amounts for specific functions, and a deficiency causes a named deficiency disease
4. An unbalanced diet means consuming too much or too little of one or more nutrients (not just eating 'unhealthy food')
5. A named consequence of an unbalanced diet beyond deficiency disease, such as type 2 diabetes (linked to excess sugar/obesity) or cardiovascular disease (linked to excess saturated fat/cholesterol)

## Key terms

- [unbalanced diet](https://www.gradenine.co.uk/glossary/unbalanced-diet)
- [carbohydrates](https://www.gradenine.co.uk/glossary/carbohydrates)
- [proteins](https://www.gradenine.co.uk/glossary/proteins)
- [lipids](https://www.gradenine.co.uk/glossary/lipids)
- [vitamins](https://www.gradenine.co.uk/glossary/vitamins)
- [minerals](https://www.gradenine.co.uk/glossary/minerals)

## Related

- [Revision notes for OCR A-Level Biology B — Advancing Biology (H422)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-student-is-investigating-the-relationship-45f4a7a5) · Published by Druglandscape Ltd.