Classification of foods according to origin, nutrients and function for SS 1

Class: SS 1
Term: First Term
Week: 2
Age: 15 years
Duration: 60 minutes
Subject: Food and Nutrition
Theme: Introduction To Foods And Nutrition
Curriculum Theme: Food Nutrients for Healthy Living
Focal competence: Applying knowledge of food nutrients based on their composition for healthy meal planning
Key competencies/values: Collaboration; ICT and Digital Competencies; Digital Competencies
Skills:

• Classifying foods based on their origin, nutrient content and functions

Previous Lesson: Foods and nutrition and Its Importance
Topic: Introduction To Foods And Nutrition: Classification Of Foods According To Origin, Nutrients And Function
Subject Matter: Classification of foods according to origin, nutrients and function

Specific Objectives

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

Cognitive Domain

• Classify foods based on their origin.
• Classify foods based on their nutrient content.
• Classify foods based on their functions.
• Analyse the effects of poor nutrition on health.

Psychomotor Domain

• Identify practical household examples for each food classification.

Affective Domain

• Appreciate the importance of proper food classification for healthy living.

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
• The HeadTeacher Scheme of work For The New Revised Senior Secondary Education Curriculum (SSEC)
• Food and Nutrition for Senior Secondary Schools Textbook

Instructional Materials

The teacher will teach this lesson with the aid of:

• Charts/posters showing food classification
• Internet-enabled devices (e.g., projector, tablets)
• Video clips on food classification and nutrition
• Actual food samples (e.g., yam, egg, groundnut, orange)

Rationale for the Lesson

This lesson is important because understanding how foods are classified helps students make informed dietary choices and plan balanced meals. It provides a fundamental framework for comprehending the role of different foods in maintaining health and preventing nutrition-related illnesses. This knowledge is crucial for promoting healthy living and addressing food safety in everyday life.

Prerequisite/Previous Knowledge

Students should have a basic understanding of what food is and why it is important for human survival.

Lesson Content/Board Summary

Classification of Foods According to Origin, Nutrients and Function

Basic Food and Nutrition Terms

1. Food: Any edible substance, usually of plant or animal origin, that provides nutrients to the body for growth, energy, and repair.
2. Nutrition: The process by which the body takes in and uses food for growth, metabolism, and repair. It involves ingestion, digestion, absorption, assimilation, and excretion.
3. Nutrient: Chemical substances found in food that are essential for the body’s growth, maintenance, and repair. Examples include carbohydrates, proteins, fats, vitamins, minerals, and water.
4. Balanced Diet: A diet that provides all the essential nutrients in the correct proportions needed to maintain health and well-being.

Classification of Foods According to Origin

Foods can be classified based on where they come from:

1. Plant Origin: Foods derived from plants.
   • Examples: Cereals (rice, maize, millet), legumes (beans, groundnuts), fruits (mango, orange, banana), vegetables (spinach, ugu, carrot), tubers (yam, cassava, potato), nuts (cashew nuts, walnuts).
2. Animal Origin: Foods derived from animals.
   • Examples: Meat (beef, chicken, goat), fish (tilapia, mackerel), eggs (chicken eggs), milk and dairy products (milk, cheese, yoghurt), seafood (prawns, crabs).
3. Mineral Origin: Essential inorganic substances obtained from the earth or water.
   • Examples: Water, salt (sodium chloride).

Classification of Foods According to Nutrients

Foods are grouped based on the predominant nutrient they provide:

1. Carbohydrate-rich Foods (Energy-giving): Provide the body with energy.
   • Examples: Yam, rice, cassava, maize, bread, pasta, sugar, honey.
   • Function: Primary source of energy for body activities.
2. Protein-rich Foods (Body-building): Essential for growth, repair of tissues, and production of enzymes and hormones.
   • Examples: Meat, fish, eggs, milk, beans, groundnuts, soyabeans.
   • Function: Builds and repairs body tissues, forms enzymes and hormones.
3. Fat and Oil-rich Foods (Energy and Protection): Provide concentrated energy, protect organs, and help absorb fat-soluble vitamins.
   • Examples: Palm oil, groundnut oil, butter, margarine, avocado, nuts, fatty fish.
   • Function: Concentrated energy source, insulates the body, protects organs, aids vitamin absorption.
4. Vitamin-rich Foods (Protective): Required in small amounts for various body functions, immunity, and overall health.
   • Examples: Fruits (citrus, pawpaw), vegetables (carrots, leafy greens), liver, milk.
   • Function: Regulate body processes, maintain good health, boost immunity.
5. Mineral-rich Foods (Protective): Essential for strong bones and teeth, blood formation, and nerve function.
   • Examples: Milk, cheese, leafy green vegetables, salt, seafood.
   • Function: Build strong bones and teeth, regulate body fluids, aid nerve function.
6. Water: Crucial for all bodily functions, including nutrient transport, temperature regulation, and waste removal.
   • Examples: Drinking water, fruits and vegetables with high water content.
   • Function: Transports nutrients, regulates body temperature, lubricates joints, aids digestion.

Classification of Foods According to Function

Foods are grouped based on their primary role in the body:

1. Energy-giving Foods: Provide the body with fuel for daily activities, warmth, and growth.
   • Examples: Carbohydrates (yam, rice, bread) and Fats/Oils (palm oil, butter).
   • Practical Household Examples: Eba, pounded yam, rice and stew, bread with butter.
2. Body-building Foods: Help in the growth and repair of body tissues, and the formation of new cells.
   • Examples: Proteins (meat, fish, eggs, beans).
   • Practical Household Examples: Beans porridge, fish stew, boiled eggs, milk drinks.
3. Protective Foods: Protect the body from diseases, regulate body processes, and maintain overall health.
   • Examples: Vitamins and Minerals (fruits, vegetables).
   • Practical Household Examples: Fruit salad, vegetable soup, fresh fruit juice.

Health Relevance of Food Classification

Understanding food classification is vital for:

1. Balanced Diet Planning: Ensures all necessary nutrients are included in meals.
2. Preventing Malnutrition: Helps identify deficiencies or excesses in diet.
3. Disease Prevention: Reduces the risk of diet-related diseases like obesity, diabetes, and heart disease.
4. Promoting Growth and Development: Especially important for children and adolescents.
5. Energy and Vitality: Ensures the body has enough energy for daily activities.

Hygiene and Safety Considerations in Food Handling

Proper hygiene and safety are essential to prevent foodborne illnesses:

1. Wash Hands: Always wash hands thoroughly with soap and water before and after handling food.
2. Cleanliness: Keep kitchen surfaces, utensils, and cutting boards clean.
3. Separate Raw and Cooked Foods: Use separate cutting boards and utensils for raw meat, poultry, and seafood to prevent cross-contamination.
4. Cook Thoroughly: Cook foods to their appropriate internal temperatures to kill harmful bacteria.
5. Chill Promptly: Refrigerate perishable foods promptly to slow bacterial growth.
6. Use Safe Water: Ensure water used for cooking and drinking is clean and safe.
7. Inspect Food: Check food for signs of spoilage (e.g., unusual smell, discolouration, mould).

Effects of Poor Nutrition

Poor nutrition, whether under-nutrition (deficiency) or over-nutrition (excess), can lead to various health problems:

1. Under-nutrition:
   • Malnutrition: General term for insufficient intake of nutrients.
   • Stunted Growth: Children fail to reach their full height potential.
   • Wasting: Children are too thin for their height.
   • Kwashiorkor: Protein deficiency, leading to swollen abdomen, skin lesions, and hair changes.
   • Marasmus: Severe calorie and protein deficiency, leading to extreme thinness.
   • Anaemia: Iron deficiency, causing fatigue, weakness, and pale skin.
   • Vitamin Deficiencies: E.g., night blindness (Vitamin A), scurvy (Vitamin C), rickets (Vitamin D).
   • Weakened Immune System: Increased susceptibility to infections.
2. Over-nutrition:
   • Obesity: Excessive body fat accumulation, leading to increased risk of heart disease, diabetes, and high blood pressure.
   • Type 2 Diabetes: Often linked to excessive sugar and calorie intake.
   • Heart Disease: High intake of saturated and trans fats can lead to high cholesterol and heart problems.
   • High Blood Pressure (Hypertension): Often associated with high sodium intake and obesity.
   • Certain Cancers: Linked to unhealthy dietary patterns.

Teaching Methods/Instructional Techniques

Discussion, Explanation, Question and Answer, Group Work, Brainstorming, Demonstration, Practical Activity.

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 mention some foods they ate for breakfast or lunch. The teacher then asks why they eat food.

Pupils’ Activity: Students respond by mentioning various foods and stating reasons like “for energy,” “to grow,” or “to stay healthy.”

Learning Point: Importance of food

Step 2: Explanation of Basic Terms

Time: 10 minutes

Teaching Skill: Explanation/Definition

Teacher’s Activity: The teacher explains basic terms like food, nutrition, nutrient, and balanced diet, using simple language and examples relevant to the students’ daily lives. The teacher uses charts or a projector to display definitions.

Pupils’ Activity: Students listen attentively, ask questions for clarification, and note down the definitions.

Learning Point: Understanding food terms

Step 3: Classification by Origin

Time: 10 minutes

Teaching Skill: Discussion/Categorisation

Teacher’s Activity: The teacher guides students to brainstorm in groups on foods they know and classify them according to their origin (plant, animal, mineral). The teacher provides examples like yam (plant), egg (animal), and salt (mineral) to initiate the discussion.

Pupils’ Activity: Students discuss in groups, identify foods, and classify them based on origin, presenting their findings to the class.

Learning Point: Food origin classification

Step 4: Classification by Nutrients

Time: 10 minutes

Teaching Skill: Explanation/Categorisation

Teacher’s Activity: The teacher explains the six classes of nutrients (carbohydrates, proteins, fats/oils, vitamins, minerals, water) and provides examples of foods rich in each, using charts or actual food samples. The teacher highlights the primary function of each nutrient.

Pupils’ Activity: Students observe the charts/samples, listen to explanations, and identify foods belonging to each nutrient group.

Learning Point: Nutrient-based classification

Step 5: Classification by Function

Time: 5 minutes

Teaching Skill: Linking/Application

Teacher’s Activity: The teacher links the nutrient classification to the functional classification (energy-giving, body-building, protective foods), giving practical household examples for each category. The teacher asks students to suggest more examples.

Pupils’ Activity: Students identify foods based on their functions in the body and contribute additional examples.

Learning Point: Food function categories

Step 6: Health Relevance and Safety

Time: 5 minutes

Teaching Skill: Discussion/Awareness

Teacher’s Activity: The teacher discusses the health relevance of understanding food classification for balanced diet planning and preventing malnutrition. The teacher also highlights key hygiene and safety considerations when handling food.

Pupils’ Activity: Students participate in the discussion, sharing their understanding of healthy eating and food safety practices.

Learning Point: Healthy eating importance

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. Classify yam, egg, and salt according to their origin.
2. Mention two foods that are primarily energy-giving and two that are body-building.
3. List three effects of poor nutrition.
4. Why is it important to wash your hands before handling food?

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Food classification understanding

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 food classification and its relevance into their notebooks.

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

Learning Point: Recording lesson content

Step 9: Conclusion

Time: 5 minutes

Teaching Skill: Summarisation

Teacher’s Activity: The teacher summarises the main points of the lesson, reiterating the importance of classifying foods for healthy living and preventing nutritional problems. The teacher encourages students to apply this knowledge in their daily food choices.

Pupils’ Activity: Students listen and ask any final questions.

Learning Point: Consolidating food classification

Continuous Assessment/Further Study

Type: Homework/Further Reading

Instruction: Answer the following questions in your notebook and research more on the specific health benefits of different vitamins and minerals.

1. Differentiate between ‘food’ and ‘nutrient’ with examples.
2. Give two examples each of foods classified by origin as: (a) Plant, (b) Animal, (c) Mineral.
3. Explain how understanding food classification can help a family plan a balanced diet.
4. Describe two common effects of under-nutrition and two effects of over-nutrition.
5. List three hygiene practices essential for safe food handling in the home.

Lesson Keywords

• Food – Any edible substance providing nutrients.
• Nutrition – Process of taking in and using food.
• Nutrient – Chemical substance in food essential for body functions.
• Balanced Diet – Diet with all nutrients in correct proportions.
• Origin – Source from which food is derived (plant, animal, mineral).
• Carbohydrates – Energy-giving foods.
• Proteins – Body-building foods.
• Vitamins – Protective foods, regulate body processes.
• Minerals – Protective foods, build bones and teeth.
• Malnutrition – Poor nutrition, either deficiency or excess.

Differentiation

For learners needing support: Provide simplified charts with fewer examples and clearer images. Pair them with stronger students during group activities. Focus on identifying basic classifications (e.g., distinguishing plant from animal origin) and the primary function of main food groups. Use visual aids and repetition.

For advanced learners: Challenge them to research specific micronutrient deficiencies prevalent in Nigeria and suggest local food sources to address them. Encourage them to create a sample balanced meal plan for a typical Nigerian family, considering cost and availability. They can also lead group discussions.

Suggested Lesson Videos

YouTube search: food classification for ss1 food and nutrition