Functions of food nutrients in the body for SS 1

Class: SS 1
Term: First Term
Week: 9
Age: 15 years
Duration: 60 minutes
Subject: Food and Nutrition
Curriculum Theme: Food Nutrients for Healthy Living
Focal competence: identifying the sources and functions of food nutrients
Key competencies/values: Communication; Collaboration; ICT and Digital Competencies; Digital Competencies
Skills:

• Selecting appropriate foods based on their nutrient content
• Identifying diet-related diseases and how to prevent them

Previous Lesson: Sources of food nutrients
Topic: Concept Of Food Nutrients: Functions Of Food Nutrients In The Body
Subject Matter: Functions of food nutrients in the body

Specific Objectives

By the end of the lesson, pupils/students should be able to:

Cognitive Domain

• Explain the functions of various food nutrients in the body.
• State the health relevance of each nutrient.

Affective Domain

• Appreciate the importance of consuming a balanced diet for good health.
• Collaborate effectively in identifying food sources of nutrients.

Psychomotor Domain

• Select appropriate foods based on their nutrient content.
• Identify practical household examples of foods rich in specific nutrients.

Reference Materials

The following resources were used in planning this lesson:

• 2025 New Revised Senior Secondary Education Curriculum (SSEC)
• Relevant State Unified Scheme of Work
• Food and Nutrition for Senior Secondary Schools, Book 1
• The HeadTeacher Scheme of work For The New Revised Senior Secondary Education Curriculum (SSEC)

Instructional Materials

The teacher will teach this lesson with the aid of:

• Chart showing classes of food nutrients
• Real food samples (e.g., vegetables, cereal grains, legumes, fruits, eggs, milk)
• Video clips on the functions of food nutrients
• Posters showing deficiency disorders (e.g., kwashiorkor, goiter)

Rationale for the Lesson

Understanding the functions of food nutrients is fundamental for making informed dietary choices and maintaining good health. This lesson helps students grasp how different nutrients contribute to body processes, enabling them to prevent diet-related diseases and promote overall well-being in their daily lives.

Prerequisite/Previous Knowledge

Pupils/students should have prior knowledge of the basic classes of food nutrients and their general sources.

Lesson Content/Board Summary

Functions of Food Nutrients in the Body

Food nutrients are essential chemical substances found in food that the body needs to function properly, grow, repair itself, and produce energy. Each class of nutrient plays specific roles vital for maintaining health.

Functions of Carbohydrates

Carbohydrates are the body’s primary source of energy. They are broken down into glucose, which fuels cells, tissues, and organs. Practical household examples include:

1. Energy Production: Provide immediate energy for physical activities and bodily functions.
2. Brain Function: Glucose is the main fuel for the brain.
3. Protein Sparing: Prevent the body from using protein for energy, allowing protein to be used for growth and repair.
4. Fibre Source: Some carbohydrates (fibre) aid digestion and prevent constipation.

Health Relevance: Adequate carbohydrate intake prevents fatigue and ensures proper organ function. Too little can lead to weakness, while excessive intake of refined carbohydrates can contribute to weight gain and diabetes.

Household Examples: Yam, rice, garri, bread, maize, potatoes.

Functions of Proteins

Proteins are the building blocks of the body, essential for growth, repair, and maintenance of tissues. They are complex molecules made up of amino acids. Practical household examples include:

1. Growth and Repair: Build and repair body tissues, muscles, skin, and hair.
2. Enzyme and Hormone Production: Form enzymes that facilitate chemical reactions and hormones that regulate body processes.
3. Antibody Formation: Produce antibodies to fight infections and strengthen the immune system.
4. Fluid Balance: Help maintain proper fluid balance in the body.
5. Energy Source: Can be used as an energy source if carbohydrates and fats are insufficient.

Health Relevance: Sufficient protein is crucial for children’s growth and recovery from illness. Deficiency can lead to conditions like kwashiorkor (swollen abdomen, stunted growth) and marasmus (severe wasting).

Household Examples: Beans, eggs, meat, fish, milk, groundnuts.

Functions of Fats and Oils

Fats and oils are concentrated sources of energy and play several vital roles in the body. Practical household examples include:

1. Energy Storage: Provide a concentrated source of energy, stored for later use.
2. Insulation: Help insulate the body and maintain body temperature.
3. Organ Protection: Cushion vital organs against shock and injury.
4. Vitamin Absorption: Aid in the absorption of fat-soluble vitamins (A, D, E, K).
5. Cell Structure: Form part of cell membranes.

Health Relevance: Essential for healthy skin and hair, and proper nerve function. Excessive intake, especially of unhealthy fats, can contribute to heart disease and obesity.

Household Examples: Palm oil, groundnut oil, butter, avocado, nuts.

Functions of Vitamins

Vitamins are organic compounds required in small quantities for various metabolic processes. They do not provide energy but are crucial for regulating body functions. Practical household examples include:

1. Immune System Support: Many vitamins (e.g., Vitamin C, D) boost immunity.
2. Vision: Vitamin A is essential for good eyesight.
3. Bone Health: Vitamin D aids calcium absorption for strong bones.
4. Blood Clotting: Vitamin K is necessary for proper blood clotting.
5. Energy Metabolism: B vitamins play a key role in converting food into energy.
6. Antioxidant Protection: Vitamins C and E protect cells from damage.

Health Relevance: Vitamin deficiencies can lead to specific diseases, such as night blindness (Vitamin A), scurvy (Vitamin C), rickets (Vitamin D), and beriberi (Vitamin B1).

Household Examples: Fruits (oranges, mangoes), vegetables (carrots, spinach), milk, liver.

Functions of Minerals

Minerals are inorganic substances required for various body functions, including bone formation, nerve function, and fluid balance. Practical household examples include:

1. Bone and Teeth Formation: Calcium and phosphorus are crucial for strong bones and teeth.
2. Blood Formation: Iron is essential for forming haemoglobin in red blood cells, preventing anaemia.
3. Nerve and Muscle Function: Sodium, potassium, and calcium are vital for nerve impulse transmission and muscle contraction.
4. Thyroid Function: Iodine is necessary for the proper functioning of the thyroid gland.
5. Fluid Balance: Sodium and potassium help regulate body fluids.

Health Relevance: Mineral deficiencies can cause serious health problems, such as anaemia (iron deficiency), goiter (iodine deficiency), and osteoporosis (calcium deficiency).

Household Examples: Salt (iodine, sodium), leafy green vegetables (iron, calcium), milk (calcium), fish (iodine).

Functions of Water

Water is the most abundant nutrient in the body and is essential for virtually all bodily functions. Practical household examples include:

1. Transportation: Transports nutrients, oxygen, and waste products throughout the body.
2. Temperature Regulation: Helps regulate body temperature through sweating.
3. Lubrication: Lubricates joints and tissues.
4. Chemical Reactions: Acts as a medium for most chemical reactions in the body.
5. Waste Removal: Helps flush out waste products through urine and faeces.

Health Relevance: Dehydration can lead to fatigue, headaches, and impaired physical and mental performance. Severe dehydration can be life-threatening. Maintaining proper hydration is a key hygiene consideration.

Household Examples: Drinking water, soups, fruits (watermelon), vegetables (cucumber).

Teaching Methods/Instructional Techniques

Discussion, Demonstration, Guided Practice, Question and Answer, Explanation, Observation, Video Presentation, Group Work.

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Questioning/Activating Prior Knowledge

Teacher’s Activity: The teacher greets the students and asks them to recall the classes of food nutrients they learned in the previous lesson. The teacher then introduces the topic: “Functions of Food Nutrients in the Body.”

Pupils’ Activity: Pupils respond to questions about classes of food nutrients and listen attentively to the introduction of the new topic.

Learning Point: Classes of food nutrients recalled

Step 2: General Functions of Food Nutrients

Time: 8 minutes

Teaching Skill: Video Presentation/Explanation

Teacher’s Activity: The teacher guides students to watch a short video clip illustrating the general importance and functions of food nutrients in the body. After the video, the teacher facilitates a brief discussion on what they observed.

Pupils’ Activity: Pupils watch the video clip and participate in the discussion, sharing their observations about the general functions of nutrients.

Learning Point: General nutrient functions observed

Step 3: Functions of Carbohydrates and Proteins

Time: 8 minutes

Teaching Skill: Explanation/Demonstration

Teacher’s Activity: The teacher explains the specific functions of carbohydrates and proteins, providing practical household examples for each. The teacher also highlights the health relevance and consequences of deficiency using the chart and posters.

Pupils’ Activity: Pupils listen, ask questions, and identify the functions and examples of carbohydrates and proteins.

Learning Point: Carbohydrate and protein functions

Step 4: Functions of Fats/Oils and Vitamins

Time: 8 minutes

Teaching Skill: Explanation/Discussion

Teacher’s Activity: The teacher continues by explaining the functions of fats/oils and vitamins. The teacher uses the chart and posters to show how these nutrients protect the body and prevent diseases, giving examples of foods rich in them.

Pupils’ Activity: Pupils pay attention, contribute to the discussion, and note the functions and health relevance of fats/oils and vitamins.

Learning Point: Fats and vitamin functions

Step 5: Functions of Minerals and Water

Time: 7 minutes

Teaching Skill: Explanation/Interactive Learning

Teacher’s Activity: The teacher explains the functions of minerals and water, emphasizing their roles in body regulation, growth, and waste removal. The teacher encourages students to share common foods rich in these nutrients.

Pupils’ Activity: Pupils listen, identify functions of minerals and water, and suggest food examples.

Learning Point: Mineral and water functions

Step 6: Identifying Nutrient Sources from Food Samples

Time: 7 minutes

Teaching Skill: Practical Demonstration/Group Work

Teacher’s Activity: The teacher displays various real food samples (e.g., yam, beans, palm oil, orange, spinach) and guides students in groups to identify which nutrient class each food primarily provides and its corresponding function.

Pupils’ Activity: Pupils work in groups to identify nutrient sources from food samples and relate them to their functions.

Learning Point: Nutrient sources identification

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. State two functions of carbohydrates in the body.
2. Explain why protein is essential for growing children.
3. Mention two fat-soluble vitamins and their functions.
4. Give two functions of water in the body.
5. Identify a food sample that is a good source of Vitamin C.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Nutrient functions assessed

Step 8: Note-Taking

Time: 10 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils/students to copy the essential Board Summary notes on the functions of food nutrients into their notebooks.

Pupils’ Activity: Pupils/students copy the notes carefully into their notebooks.

Learning Point: Nutrient functions recorded

Step 9: Conclusion

Time: 4 minutes

Teaching Skill: Reinforcement

Teacher’s Activity: The teacher summarises the key functions of all food nutrients and reiterates the importance of eating a balanced diet for overall health and prevention of deficiency diseases. The teacher encourages students to apply this knowledge in their daily food choices.

Pupils’ Activity: Pupils listen and reflect on the importance of balanced nutrition.

Learning Point: Balanced diet importance reinforced

Continuous Assessment/Further Study

Type: Homework/Further Reading

Instruction: Answer the following questions in your notebook:

1. Research and list three deficiency diseases caused by a lack of specific vitamins or minerals, stating the nutrient and its function.
2. Plan a simple balanced meal for your family, ensuring it includes at least one food item from each major nutrient group (carbohydrates, proteins, fats, vitamins, minerals).
3. Explain how understanding the functions of food nutrients can help you make healthier food choices.

Lesson Keywords

• Carbohydrates – Primary source of energy for the body.
• Proteins – Building blocks for growth, repair, and maintenance of tissues.
• Fats and Oils – Concentrated energy source, insulation, and organ protection.
• Vitamins – Organic compounds regulating body processes, essential for health.
• Minerals – Inorganic substances for bone formation, nerve function, and fluid balance.
• Water – Essential for transportation, temperature regulation, and waste removal.
• Deficiency diseases – Illnesses caused by a lack of specific nutrients.
• Balanced diet – A diet containing all essential nutrients in correct proportions.

Differentiation

For students needing support: Provide a simplified chart with key functions and examples for each nutrient. Pair them with stronger students during group activities. Focus on identifying one key function for each nutrient.
For advanced students: Encourage them to research specific metabolic pathways where nutrients are involved or investigate the nutritional content of less common Nigerian food items.

Suggested Lesson Videos

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