Nutrition is the science of food and its relationship to health. It involves the intake, digestion, absorption, metabolism, and utilization of nutrients by the body for growth, maintenance, and overall well-being.
Importance of Nutrition in Nursing
In nursing, nutrition plays a vital role in promoting health, preventing diseases, and assisting in the recovery process. Proper nutrition is essential for maintaining bodily functions, boosting immunity, and supporting the healing process.
Basic Nutrients and Their Functions
Carbohydrates – Provide energy (e.g., rice, bread, potatoes).
Proteins – Essential for growth, repair, and maintenance of body tissues (e.g., meat, fish, eggs, legumes).
Fats – Provide concentrated energy and aid in the absorption of fat-soluble vitamins (e.g., oils, butter, nuts).
Vitamins – Regulate body processes and prevent deficiencies (e.g., Vitamin A for vision, Vitamin C for immunity).
Minerals – Support various bodily functions (e.g., calcium for bone health, iron for hemoglobin production).
Water – Essential for hydration, digestion, and temperature regulation.
Nutritional Needs Across the Lifespan
Infants and Children – Require high protein and calorie intake for growth.
Adolescents – Need balanced nutrition for hormonal changes and development.
Adults – Require a well-balanced diet to maintain health and prevent chronic diseases.
Elderly – Need more fiber, calcium, and hydration while monitoring caloric intake.
Role of Nurses in Nutrition
Assess patients’ nutritional status and dietary needs.
Provide nutritional education to patients and caregivers.
Assist in planning and implementing dietary modifications.
Monitor nutritional intake and identify signs of malnutrition.
Collaborate with dietitians and healthcare teams for better patient outcomes.
Common Nutritional Disorders in Nursing Practice
Malnutrition – Deficiency or excess of essential nutrients.
Obesity – Excess body fat leading to health complications.
Anemia – Iron deficiency affecting oxygen transport.
Hypertension – Sodium control to prevent cardiovascular diseases.
Definition of Nutrition
What is Nutrition?
Nutrition is the science of food, nutrients, and their effect on the body. It involves the study of how the body ingests, digests, absorbs, transports, utilizes, and excretes nutrients and other substances from food. Proper nutrition ensures that the body gets the required nutrients for energy, growth, maintenance, and repair.
Key Aspects of Nutrition
Nutrient Intake – Consuming food with essential nutrients.
Digestion – Breaking down food into absorbable forms.
Absorption – Transporting nutrients into the bloodstream.
Metabolism – Converting food into energy and body components.
Excretion – Eliminating waste products.
Types of Nutrition
Autotrophic Nutrition – Organisms (like plants) synthesize their food through photosynthesis.
Heterotrophic Nutrition – Organisms (like humans) consume food for energy and growth.
Nutrients and Their Functions
Nutrients are substances required for proper body functioning. They are classified as:
Macronutrients (needed in large amounts)
Carbohydrates – Provide energy (e.g., rice, wheat, potatoes).
Proteins – Build and repair tissues (e.g., meat, eggs, legumes).
Fats – Provide long-term energy and cell function (e.g., oil, butter, nuts).
Water – Essential for hydration, digestion, and temperature regulation.
Micronutrients (needed in small amounts)
Vitamins – Help in body functions (e.g., Vitamin A for vision, Vitamin D for bone health).
Minerals – Maintain body processes (e.g., calcium for bones, iron for blood).
Importance of Nutrition
Supports growth and development.
Strengthens the immune system.
Helps prevent diseases like diabetes, heart disease, and obesity.
Enhances mental and physical performance.
Aids in wound healing and recovery.
Definition of Health
What is Health?
Health is a state of complete physical, mental, and social well-being, not just the absence of disease or infirmity (WHO, 1948). It includes overall wellness and the ability to lead a productive life.
Dimensions of Health
Physical Health – Proper functioning of the body and organs.
Mental Health – Psychological well-being and emotional balance.
Social Health – Healthy relationships and effective communication.
Spiritual Health – Personal beliefs and values that provide meaning in life.
Environmental Health – Clean surroundings and safe living conditions.
Determinants of Health
Genetic Factors – Hereditary traits and diseases.
Lifestyle Choices – Diet, exercise, and habits like smoking.
Socioeconomic Status – Income, education, and occupation.
Healthcare Access – Availability of medical facilities and services.
Environmental Factors – Pollution, sanitation, and living conditions.
Importance of Health
Increases life expectancy.
Improves quality of life.
Reduces the risk of chronic diseases.
Enhances mental clarity and emotional stability.
Promotes economic and social productivity.
Relationship Between Nutrition and Health
Good Nutrition = Better Health – A balanced diet boosts immunity, prevents deficiencies, and promotes longevity.
Poor Nutrition = Illness and Disease – Deficiencies lead to conditions like anemia, rickets, and malnutrition.
Nutritional Therapy – Used in managing diseases like diabetes, obesity, and hypertension.
Malnutrition:
Definition of Malnutrition
Malnutrition refers to a condition that results from an imbalance in nutrient intake, either due to deficiency, excess, or improper utilization of nutrients. It can lead to various health issues, including growth retardation, weakened immunity, and increased susceptibility to diseases.
According to the World Health Organization (WHO), malnutrition includes undernutrition (wasting, stunting, underweight), micronutrient deficiencies, and overnutrition (obesity, overweight).
Types of Malnutrition
1. Undernutrition (Nutritional Deficiencies)
Occurs due to inadequate intake of essential nutrients. It includes:
Wasting – Low weight for height (acute malnutrition).
Stunting – Low height for age (chronic malnutrition).
Underweight – Low weight for age (can be due to both stunting and wasting).
Micronutrient Deficiencies – Lack of essential vitamins and minerals (e.g., iron, vitamin A, iodine).
2. Overnutrition
Occurs due to excessive intake of nutrients, leading to obesity and associated diseases:
Overweight & Obesity – Excess body fat caused by high-calorie intake and low physical activity.
Metabolic Disorders – Diabetes, hypertension, and cardiovascular diseases linked to excess nutrients.
Causes of Malnutrition
1. Dietary Causes
Inadequate food intake – Insufficient quantity and quality of food.
Poor dietary diversity – Lack of variety in meals, leading to micronutrient deficiencies.
Overeating or Unhealthy Diet – Consumption of high-calorie, low-nutrient foods.
2. Socioeconomic Factors
Poverty – Limited access to nutritious food.
Lack of Education – Poor knowledge about balanced diets and healthy eating habits.
Food Insecurity – Unavailability of food due to environmental and economic conditions.
3. Medical Conditions
Infections and Diseases – Conditions like tuberculosis, HIV/AIDS, and cancer increase nutrient demand.
Gastrointestinal Disorders – Conditions like Crohn’s disease or celiac disease affect nutrient absorption.
Mental Health Issues – Eating disorders such as anorexia nervosa and bulimia lead to malnutrition.
4. Poor Sanitation and Hygiene
Frequent Infections – Intestinal infections (e.g., diarrhea) lead to nutrient loss.
Unsafe Drinking Water – Causes diseases that impair nutrient absorption.
5. Special Conditions
Pregnancy and Lactation – Increased nutritional requirements.
Infants and Children – High risk due to rapid growth.
Elderly Population – Poor appetite and digestive issues leading to malnutrition.
Signs and Symptoms of Malnutrition
1. Symptoms of Undernutrition
Weight Loss – Sudden or gradual weight loss.
Muscle Wasting – Loss of muscle mass and weakness.
Fatigue and Weakness – Lack of energy and endurance.
Slow Growth in Children – Stunted height and delayed milestones.
Weak Immunity – Increased susceptibility to infections.
Dry Skin and Hair Loss – Due to lack of essential nutrients.
Delayed Wound Healing – Poor tissue repair.
2. Symptoms of Overnutrition
Excess Body Fat – Particularly around the abdomen.
High Blood Pressure (Hypertension) – Due to excessive sodium and fat intake.
Diabetes Mellitus (Type 2 Diabetes) – Linked to excess sugar and fat consumption.
Joint Pain and Mobility Issues – Due to increased body weight.
Heart Diseases – Risk of stroke, heart attack, and atherosclerosis.
Effects of Malnutrition on the Body
1. Growth and Development Issues
Stunting and developmental delays in children.
Cognitive impairments affecting learning and memory.
2. Immune System Weakness
Increased frequency and severity of infections.
Delayed recovery from illnesses.
3. Metabolic and Organ Damage
Liver and kidney damage in extreme malnutrition cases.
Increased risk of diabetes, heart disease, and metabolic syndrome in overnutrition.
4. Mental and Emotional Impact
Depression, anxiety, and behavioral issues.
Reduced productivity and concentration.
Diagnosis of Malnutrition
1. Clinical Assessment
Body Mass Index (BMI) – Underweight (<18.5), Normal (18.5-24.9), Overweight (25-29.9), Obese (>30).
Mid-Upper Arm Circumference (MUAC) – Used for assessing malnutrition in children.
Skinfold Thickness Test – Measures fat reserves.
2. Laboratory Tests
Blood Tests – To check for anemia, protein levels, and vitamin deficiencies.
Serum Albumin Test – Evaluates protein status.
Iron, Vitamin, and Mineral Levels – Detects specific deficiencies.
3. Dietary Assessment
24-hour Recall – Evaluating food intake over a day.
Food Frequency Questionnaire (FFQ) – Analyzes long-term dietary habits.
Prevention and Management of Malnutrition
1. Nutritional Interventions
Balanced Diet – Including all macronutrients and micronutrients.
Nutrient Supplementation – Vitamin A, iron, iodine, and folic acid for deficiency management.
Nutritional Assessment – Identifying patients at risk.
Dietary Counseling – Educating patients on healthy eating.
Monitoring Growth and Development – Particularly in children and pregnant women.
Administering Supplements and Therapeutic Diets – Based on patient needs.
Collaborating with Dietitians and Physicians – Ensuring holistic nutritional care.
Under-Nutrition & Over-Nutrition:
Introduction to Malnutrition
Malnutrition refers to an imbalance in nutrient intake, which can be either deficiency (under-nutrition) or excess (over-nutrition). It affects physical growth, mental development, and overall health. Malnutrition is a major global health concern, especially in children, pregnant women, and the elderly.
1. UNDER-NUTRITION
Definition
Under-nutrition occurs when the body does not receive enough nutrients, leading to weight loss, muscle wasting, stunted growth, and weakened immunity. It results from inadequate food intake, poor absorption, or excessive loss of nutrients due to illness.
Types of Under-Nutrition
Acute Malnutrition (Wasting)
Definition: Sudden weight loss due to severe deficiency of calories and proteins.
Symptoms: Low weight for height, extreme thinness, and muscle wasting.
Example: Severe Acute Malnutrition (SAM), Moderate Acute Malnutrition (MAM).
Chronic Malnutrition (Stunting)
Definition: Long-term deficiency of nutrients leading to poor growth.
Symptoms: Short height for age, delayed development, and poor cognitive function.
Protein-Energy Malnutrition (PEM)
Kwashiorkor: Protein deficiency leading to swollen belly, edema, skin lesions, and liver enlargement.
Marasmus: Severe calorie and protein deficiency causing extreme thinness, muscle wasting, and weakness.
Micronutrient Deficiencies
Iron Deficiency Anemia – Causes fatigue, pale skin, and weakness.
Vitamin A Deficiency – Leads to night blindness, dry eyes, and weakened immunity.
Iodine Deficiency – Causes goiter, mental retardation, and thyroid disorders.
Zinc Deficiency – Results in growth retardation, diarrhea, and immune dysfunction.
Causes of Under-Nutrition
1. Dietary Causes
Insufficient food intake due to poverty or lack of availability.
Poor-quality diets with low protein and micronutrient content.
Improved maternal nutrition during pregnancy and lactation.
Health education about balanced diets and food hygiene.
Community-based nutrition programs.
2. OVER-NUTRITION
Definition
Over-nutrition occurs when the body receives excessive calories or nutrients, leading to obesity and diet-related diseases like diabetes, hypertension, and heart disease. It results from overeating, lack of physical activity, and poor dietary choices.
Types of Over-Nutrition
Overweight and Obesity
Definition: Excess body fat accumulation.
Measurement: Body Mass Index (BMI) – Overweight (BMI 25-29.9), Obesity (BMI ≥ 30).
Strength training – Muscle building to boost metabolism.
3. Medical and Lifestyle Interventions
Behavioral therapy – Counseling for emotional eating.
Medications for obesity (only in severe cases).
Surgical options – Gastric bypass, bariatric surgery for morbid obesity.
4. Preventive Measures
Public awareness about healthy eating.
Healthy meal planning in schools, workplaces.
Regular health check-ups for early detection.
Role of Nutrition in Maintaining Health
Introduction
Nutrition plays a fundamental role in maintaining health and preventing diseases. A well-balanced diet provides the essential nutrients required for growth, energy production, immune function, and overall well-being. Proper nutrition ensures optimal bodily functions and reduces the risk of malnutrition-related disorders.
Key Roles of Nutrition in Health Maintenance
1. Provides Energy for Daily Activities
Carbohydrates, fats, and proteins serve as the primary sources of energy.
Carbohydrates are the body’s preferred energy source (e.g., rice, wheat, fruits).
Fats provide long-term energy storage and support cell function.
Proteins contribute to energy when carbohydrate intake is insufficient.
2. Supports Growth and Development
Proteins, vitamins, and minerals are essential for the growth and repair of body tissues.
Children, adolescents, and pregnant women require high-quality nutrition for proper development.
Calcium and phosphorus are crucial for bone development and strength.
3. Strengthens the Immune System
A well-nourished body is better equipped to fight infections and diseases.
Vitamin C (found in citrus fruits) boosts immune function.
Zinc and Iron play a role in immune cell production and function.
Protein supports the production of antibodies and enzymes.
4. Maintains Organ Function
Heart Health: Omega-3 fatty acids (found in fish, nuts) help lower cholesterol and prevent cardiovascular diseases.
Brain Health: B vitamins, omega-3 fatty acids, and antioxidants enhance memory, cognitive function, and mental well-being.
Liver and Kidney Health: Adequate hydration and balanced nutrient intake prevent liver damage and kidney disorders.
5. Prevents Nutrient Deficiency Diseases
Iron Deficiency (Anemia): Results in fatigue and weakness, prevented by consuming iron-rich foods (e.g., spinach, red meat).
Vitamin A Deficiency: Causes night blindness; found in carrots, eggs, and dairy.
Iodine Deficiency: Leads to goiter and developmental issues, prevented by iodized salt intake.
Calcium Deficiency: Leads to osteoporosis, prevented by dairy products and leafy greens.
6. Promotes Digestive Health
Fiber-rich foods (whole grains, vegetables, fruits) prevent constipation and support gut health.
Probiotics (yogurt, fermented foods) maintain a healthy balance of gut bacteria.
Adequate water intake ensures proper digestion and prevents dehydration.
7. Supports Healthy Weight Management
Balanced nutrition prevents both obesity and undernutrition.
Portion control and nutrient-dense foods prevent excessive weight gain.
Regular physical activity combined with a healthy diet maintains an ideal weight.
8. Regulates Hormonal Balance
Fats and proteins help in hormone production.
Iodine and selenium support thyroid function.
Vitamin D and calcium regulate bone and muscle health.
9. Reduces the Risk of Chronic Diseases
Heart Disease: Controlled by reducing saturated fats, cholesterol, and salt intake.
Diabetes: Managed by regulating carbohydrate and sugar intake.
Hypertension: Controlled by maintaining a low-sodium diet.
Cancer Prevention: Antioxidants (from fruits and vegetables) protect cells from damage.
10. Enhances Mental and Emotional Well-being
B vitamins and omega-3 fatty acids reduce the risk of depression and anxiety.
Amino acids from proteins help in neurotransmitter production, improving mood.
Balanced blood sugar levels prevent mood swings and fatigue.
Factors Affecting Food and Nutrition
Introduction
Food and nutrition are influenced by several factors, including biological, social, cultural, economic, and environmental determinants. Understanding these factors is essential for ensuring proper dietary choices, preventing malnutrition, and promoting overall health.
1. Biological Factors
a. Age and Life Stage
Infants and Children – Require high-protein, vitamin, and mineral-rich diets for growth.
Adolescents – Need increased calorie and protein intake due to rapid growth and hormonal changes.
Adults – Require balanced diets to maintain health and prevent chronic diseases.
Elderly – Need nutrient-dense foods with lower calories to support metabolism and prevent deficiencies.
b. Gender
Men usually require higher calorie intake due to greater muscle mass.
Women need more iron and calcium due to menstruation, pregnancy, and menopause.
c. Pregnancy and Lactation
Increased demand for iron, folic acid, calcium, and protein for fetal development and milk production.
d. Health Status and Metabolism
Individuals with high metabolic rates require more calories.
FDA (Food and Drug Administration) and FSSAI (Food Safety and Standards Authority of India) regulate food safety.
Poor food quality and adulteration affect health.
b. Public Health Programs
Government initiatives (e.g., Mid-Day Meal Scheme, National Nutrition Mission) improve nutritional status.
c. Food Subsidies
Programs like ration systems and food coupons ensure food security for low-income groups.
7. Lifestyle and Eating Behavior
a. Urban vs. Rural Diets
Urban areas – Higher consumption of processed and fast foods.
Rural areas – More reliance on homegrown and traditional foods.
b. Fast Food and Convenience Foods
Increased intake of junk food leads to obesity and nutrient deficiencies.
c. Meal Patterns
Skipping meals and irregular eating habits affect nutrient absorption.
Nutrients: Introduction and Classification
Introduction to Nutrients
Nutrients are substances that the body requires to grow, develop, function properly, and maintain overall health. They provide energy, build and repair tissues, and regulate body processes.
A balanced diet consists of all essential nutrients in the right proportions to maintain good health and prevent diseases.
Classification of Nutrients
Nutrients are classified into two major categories:
1. Macronutrients (Required in Large Amounts)
These provide energy and are essential for growth and bodily functions.
Carbohydrates
Proteins
Fats
Water
2. Micronutrients (Required in Small Amounts)
These help in metabolic processes, immunity, and overall well-being.
Iodine – Thyroid hormone production (e.g., iodized salt).
Fluoride – Dental health (e.g., fluoridated water).
Macro and Micronutrients:
Introduction
Nutrients are substances obtained from food that are essential for growth, development, energy production, and maintaining body functions. They are classified into two main categories:
Macronutrients – Required in large amounts, providing energy and building body structures.
Micronutrients – Required in small amounts, essential for metabolic functions and disease prevention.
A balanced diet ensures the right intake of both macronutrients and micronutrients to maintain optimal health.
1. Macronutrients (Needed in Large Amounts)
Macronutrients provide the energy and structural components required for body functions. They include:
Carbohydrates
Proteins
Fats
Water
1. Carbohydrates
Primary function: Provide energy for body functions.
Primary function: Essential for hydration, digestion, circulation, and temperature regulation.
Sources: Water, fruits, vegetables, soups.
Daily Requirement:2-3 liters per day.
Importance: Helps in nutrient transport, waste removal, and body cooling.
2. Micronutrients (Needed in Small Amounts)
Micronutrients do not provide energy but are essential for growth, immunity, and metabolic functions.
They include:
Vitamins
Minerals
1. Vitamins
Vitamins are organic compounds that help in enzyme functions and prevent diseases.
Types of Vitamins:
a. Fat-Soluble Vitamins (Stored in Fat, Need Fat for Absorption)
Vitamin
Function
Sources
Deficiency Diseases
Vitamin A
Vision, immune function
Carrots, eggs, dairy
Night blindness
Vitamin D
Bone health, calcium absorption
Sunlight, fish
Rickets, osteoporosis
Vitamin E
Antioxidant, skin health
Nuts, vegetable oils
Nerve damage
Vitamin K
Blood clotting
Leafy greens
Excessive bleeding
b. Water-Soluble Vitamins (Not Stored, Need Daily Intake)
Vitamin
Function
Sources
Deficiency Diseases
Vitamin C
Immunity, wound healing
Citrus fruits
Scurvy
Vitamin B1 (Thiamine)
Nerve function
Whole grains, pork
Beriberi
Vitamin B2 (Riboflavin)
Energy production
Dairy, eggs
Cracked lips, anemia
Vitamin B3 (Niacin)
Digestion, skin health
Meat, nuts
Pellagra
Vitamin B6 (Pyridoxine)
Brain function
Bananas, chicken
Nervous disorders
Vitamin B12 (Cobalamin)
RBC production, nerve function
Meat, dairy
Pernicious anemia
Folic Acid (B9)
Fetal development
Green vegetables
Neural tube defects
2. Minerals
Minerals are inorganic elements essential for metabolic processes and bone health.
Types of Minerals:
a. Macrominerals (Needed in Large Amounts)
Mineral
Function
Sources
Deficiency Diseases
Calcium
Bone & teeth health
Dairy, green vegetables
Osteoporosis, rickets
Potassium
Muscle function, heart health
Bananas, potatoes
Weakness, cramps
Sodium
Nerve function, fluid balance
Salt
Low blood pressure
Magnesium
Enzyme function, muscle health
Nuts, whole grains
Muscle weakness
b. Microminerals (Trace Elements, Needed in Small Amounts)
Mineral
Function
Sources
Deficiency Diseases
Iron
Hemoglobin formation
Red meat, spinach
Anemia
Zinc
Wound healing, immunity
Seafood, nuts
Growth retardation
Iodine
Thyroid hormone production
Iodized salt
Goiter
Fluoride
Dental health
Fluoridated water
Tooth decay
Differences Between Macronutrients and Micronutrients
Feature
Macronutrients
Micronutrients
Amount Required
Large amounts
Small amounts
Energy Contribution
Provide energy
No energy contribution
Types
Carbohydrates, Proteins, Fats, Water
Vitamins, Minerals
Function
Growth, energy production, body functions
Metabolic regulation, disease prevention
Examples
Rice, meat, butter, water
Vitamin A, Iron, Zinc
Organic and Inorganic Nutrients:
Introduction
Nutrients are essential substances that the body needs for growth, energy production, metabolism, and overall health. These nutrients are categorized as organic and inorganic based on their chemical composition.
1. Organic Nutrients – Contain carbon and are derived from living organisms.
2. Inorganic Nutrients – Do not contain carbon and originate from non-living sources like soil and water.
1. Organic Nutrients
Organic nutrients are carbon-based compounds found in living organisms (plants and animals). These include:
Carbohydrates
Proteins
Fats (Lipids)
Vitamins
1. Carbohydrates
Definition: Organic compounds made of carbon, hydrogen, and oxygen.
Function: Primary source of energy.
Sources: Rice, wheat, fruits, potatoes, honey.
Types:
Simple Carbohydrates (Sugars) – Quick energy (e.g., glucose, fructose).
Definition: Organic compounds made of fatty acids and glycerol.
Function: Provide long-term energy, absorb fat-soluble vitamins, protect organs.
Sources: Butter, oil, nuts, seeds, fatty fish.
Types:
Saturated Fats – Found in animal fats, butter (increase cholesterol).
Unsaturated Fats – Found in plant oils, nuts, fish (heart-healthy).
Trans Fats – Found in processed foods (harmful to health).
4. Vitamins
Definition: Organic compounds required in small amounts for metabolism.
Function: Regulate body functions and prevent deficiency diseases.
Types:
Fat-Soluble Vitamins (Stored in Fat) – A, D, E, K.
Water-Soluble Vitamins (Not Stored, Need Daily Intake) – C, B-complex.
2. Inorganic Nutrients
Inorganic nutrients do not contain carbon and are derived from non-living sources like water, soil, and minerals. These include:
Minerals
Water
1. Minerals
Definition: Inorganic elements essential for body functions.
Function: Bone strength, nerve transmission, muscle function, enzyme activation.
Sources: Dairy, meat, vegetables, water.
Types of Minerals
a. Macrominerals (Needed in Large Amounts)
Mineral
Function
Sources
Deficiency Diseases
Calcium
Bone & teeth health
Dairy, green vegetables
Osteoporosis
Potassium
Muscle function, heart health
Bananas, potatoes
Weakness
Sodium
Nerve function, fluid balance
Salt
Low BP
Magnesium
Enzyme function
Nuts, whole grains
Muscle weakness
b. Microminerals (Trace Elements, Needed in Small Amounts)
Mineral
Function
Sources
Deficiency Diseases
Iron
Hemoglobin formation
Red meat, spinach
Anemia
Zinc
Wound healing, immunity
Seafood, nuts
Growth retardation
Iodine
Thyroid hormone production
Iodized salt
Goiter
Fluoride
Dental health
Fluoridated water
Tooth decay
2. Water
Definition: A vital inorganic nutrient required for life.
Function: Hydration, digestion, temperature regulation, waste removal.
Sources: Drinking water, fruits, vegetables.
Daily Requirement:2-3 liters per day.
Differences Between Organic and Inorganic Nutrients
Feature
Organic Nutrients
Inorganic Nutrients
Carbon Content
Contain carbon
Do not contain carbon
Source
Derived from living organisms (plants, animals)
Derived from non-living sources (soil, water)
Types
Carbohydrates, Proteins, Fats, Vitamins
Minerals, Water
Function
Provide energy, growth, and metabolism
Support structure, hydration, enzyme function
Examples
Rice, meat, nuts, fruits, dairy
Salt, water, iron, calcium
Energy-Yielding and Non-Energy-Yielding Nutrients
Introduction
Nutrients are essential for maintaining bodily functions, supporting growth, and preventing diseases. Based on their role in energy production, nutrients are categorized into:
Energy-Yielding Nutrients – Provide calories to fuel bodily functions.
Non-Energy-Yielding Nutrients – Do not provide calories but are essential for metabolic processes and overall health.
1. Energy-Yielding Nutrients
These nutrients supply energy (calories) to the body, enabling it to perform functions such as movement, digestion, and cell repair. The main energy-yielding nutrients include:
Importance: Helps in nutrient transport, cellular function, and detoxification.
Differences Between Energy-Yielding and Non-Energy-Yielding Nutrients
Feature
Energy-Yielding Nutrients
Non-Energy-Yielding Nutrients
Caloric Contribution
Provide energy (calories)
Do not provide calories
Types
Carbohydrates, Proteins, Fats
Vitamins, Minerals, Water
Function
Fuel body functions and physical activity
Support metabolism, immunity, and cell function
Caloric Value
4 kcal/g (Carbs & Proteins), 9 kcal/g (Fats)
0 kcal/g
Examples
Rice, meat, butter, oil
Vitamin C, Calcium, Water
Food: Classification and Food Groups
Introduction
Food is any substance consumed to provide nutrients and energy for the body’s growth, maintenance, and overall well-being. It contains essential macronutrients (carbohydrates, proteins, fats) and micronutrients (vitamins and minerals) required for survival and health.
To ensure a balanced diet, food is classified into different food groups based on their nutritional composition and function.
Classification of Food
Food can be classified based on different criteria:
1. Based on Nutrient Function
Energy-Giving Foods – Provide energy for body functions (Carbohydrates, Fats).
Body-Building Foods – Help in growth, muscle repair, and maintenance (Proteins).
Protective and Regulatory Foods – Provide vitamins and minerals for disease prevention and body regulation.
Junk Foods – High in fats, sugars, and salt but low in nutrients (e.g., fast food, chips, soda).
Food Groups
The classification of food into groups helps in meal planning and maintaining a balanced diet.
1. Five Food Groups (Balanced Diet Approach)
According to nutrition guidelines, food is divided into five major groups:
Food Group
Examples
Nutritional Benefits
Cereals, Grains, and Starchy Foods
Rice, wheat, oats, potatoes, corn
Provide carbohydrates for energy
Proteins (Pulses, Meat, and Dairy)
Lentils, beans, meat, fish, eggs, milk
Help in muscle building and repair
Vegetables
Leafy greens, carrots, tomatoes, broccoli
Provide vitamins, minerals, and fiber for immunity
Fruits
Apples, bananas, oranges, berries
Rich in vitamins (C, A), fiber, and antioxidants
Fats and Oils
Butter, ghee, vegetable oils, nuts
Provide energy and aid in vitamin absorption
2. Three Food Groups (Simplified Approach)
Food can also be categorized into three basic groups based on their function:
Food Group
Examples
Function
Energy-Giving Foods
Rice, wheat, sugar, fats, oils
Provide calories and energy for daily activities
Body-Building Foods
Meat, fish, dairy, eggs, legumes
Help in growth and repair of body tissues
Protective Foods
Fruits, vegetables, dairy
Boost immunity and regulate body functions
3. Indian Food Group Classification
The Indian Council of Medical Research (ICMR) and National Institute of Nutrition (NIN) classify food into seven groups for dietary planning:
Food Group
Examples
Nutrient Contribution
Cereals and Millets
Rice, wheat, maize, jowar
Energy (carbohydrates)
Pulses and Legumes
Lentils, chickpeas, soybeans
Proteins, fiber
Milk and Dairy Products
Milk, cheese, yogurt
Proteins, calcium
Meat, Fish, and Eggs
Chicken, fish, eggs
High-quality proteins, iron
Fruits and Vegetables
Green leafy vegetables, citrus fruits
Vitamins, minerals, antioxidants
Fats and Oils
Butter, ghee, vegetable oil
Energy, essential fatty acids
Sugars and Sweeteners
Honey, jaggery, sugar
Quick energy source
Importance of Food Groups in a Balanced Diet
Ensures variety in the diet for optimal nutrition.
Prevents nutrient deficiencies and associated diseases.
Maintains healthy body weight by balancing energy intake and expenditure.
Supports overall growth, development, and immunity.
Origin of Food: Classification and Sources
Introduction
Food originates from various natural sources, including plants, animals, and other natural environments. The classification of food based on its origin helps us understand its nutritional composition, availability, and dietary significance.
Food can be classified based on its biological origin, processing, and production methods.
Classification of Food Based on Origin
Food can be broadly classified into three categories based on its source:
1. Plant-Based Foods
2. Animal-Based Foods
3. Other Natural Sources (Microbial and Mineral-Based Foods)
1. Plant-Based Foods
Plant-based foods come from crops, trees, and other vegetation. These are rich in carbohydrates, fiber, vitamins, and minerals.
Types of Plant-Based Foods
Category
Examples
Nutritional Benefits
Cereals and Grains
Rice, wheat, maize, oats, barley
High in carbohydrates, fiber, and some proteins
Pulses and Legumes
Lentils, chickpeas, beans, peas
Rich in proteins, fiber, and iron
Fruits
Apples, bananas, mangoes, oranges
Provide vitamins (A, C), fiber, and antioxidants
Vegetables
Spinach, carrots, tomatoes, potatoes
Rich in vitamins, minerals, and fiber
Nuts and Seeds
Almonds, walnuts, flaxseeds, sunflower seeds
Good source of healthy fats, proteins, and minerals
Spices and Herbs
Turmeric, ginger, garlic, basil, cinnamon
Used for flavoring, medicinal properties, and digestion
Oils from Plants
Olive oil, mustard oil, coconut oil
Provide essential fatty acids and vitamin E
Sugars and Sweeteners
Sugarcane, honey, jaggery, maple syrup
Quick source of energy
Importance of Plant-Based Foods
Rich in fiber, promoting digestion.
Provide essential vitamins and minerals.
Contain antioxidants that prevent diseases.
Good source of phytonutrients that enhance immunity.
2. Animal-Based Foods
Animal-based foods come from livestock, poultry, fish, and dairy sources. These foods are rich in proteins, fats, vitamins (B12, D), and minerals (iron, calcium, zinc).
Types of Animal-Based Foods
Category
Examples
Nutritional Benefits
Meat
Chicken, beef, pork, mutton
High-quality protein, iron, and vitamin B12
Fish and Seafood
Salmon, tuna, prawns, crabs
Rich in omega-3 fatty acids, iodine, and proteins
Eggs
Hen eggs, quail eggs, duck eggs
Excellent source of protein, vitamin D, and choline
Milk and Dairy Products
Milk, cheese, butter, yogurt
High in calcium, proteins, and probiotics
Animal Fats
Ghee, lard, tallow
Provide energy and fat-soluble vitamins (A, D, E, K)
Importance of Animal-Based Foods
Complete protein source with all essential amino acids.
Rich in vitamin B12, which is absent in plant-based foods.
Supports muscle growth and repair.
Strengthens bones and teeth due to high calcium content.
3. Other Natural Sources (Microbial and Mineral-Based Foods)
Certain foods come from microorganisms, fungi, and minerals. These are important for food processing, digestion, and health benefits.
Types of Microbial and Mineral-Based Foods
Category
Examples
Nutritional Benefits
Fungi-Based Foods
Mushrooms, yeast
Provide protein, vitamin D, and minerals
Fermented Foods
Yogurt, kimchi, kefir, cheese
Contain probiotics that aid digestion
Edible Algae
Spirulina, seaweed
High in protein, iodine, and omega-3 fatty acids
Mineral-Based Foods
Salt, water, calcium carbonate
Essential for hydration and body functions
Importance of Microbial and Mineral-Based Foods
Improve digestion through probiotics.
Enhance immunity and gut health.
Provide essential minerals like iodine and calcium.