Basics of Energy Metabolism – Nutrition & Dietetics (B.Sc
/ M.Sc Exam-Oriented Notes)
Course:
B.Sc / M.Sc Nutrition & Dietetics
Subject:
Nutritional Biochemistry / Human Nutrition
Unit:
Basics of Energy Metabolism, Nutrition & Dietetics
Contents Covered
• Units of measurement of energy
• Calorific value of food
• Basal Metabolic Rate (BMR)
• Factors affecting BMR
• Specific Dynamic Action (SDA) of food
• Calculation of energy requirement
• Balanced diet
• Nutrition in health and disease
• Protein Energy Malnutrition (PEM)
Type of Notes
Exam-Oriented | Simple Language | Concept-Based
Suitable for:
B.Sc & M.Sc Nutrition / Clinical Nutrition / Dietetics Students
Prepared for academic learning and examination reference.
, NUTRITIONAL BIOCHEMISTRY
Basics of Energy Metabolism
1. Energy and Its Measurement
Meaning of Energy
Energy is defined as the capacity of the body to do work. All vital functions of the human body require
energy for their proper functioning. These functions include breathing, circulation of blood, digestion
and absorption of food, physical activity, maintenance of body temperature, growth, repair of tissues,
and overall metabolism.
The body obtains energy mainly from macronutrients present in food, namely carbohydrates, proteins,
and fats. Without adequate energy intake, normal body functions cannot be maintained.
Units of Measurement of Energy
Energy can be measured in different units. In nutrition and dietetics, the commonly used units are
calorie, kilocalorie, and joule.
1. Calorie (cal)
The calorie (cal) is the smallest unit of energy. It is defined as the amount of heat required to raise the
temperature of 1 gram of water by 1°C.
Because this unit is very small, it is not practical for expressing the daily energy needs of the human
body. Therefore, it is rarely used in nutrition.
2. Kilocalorie (kcal)
The kilocalorie (kcal) is the most commonly used unit of energy in nutrition.
• 1 kilocalorie (kcal) = 1000 calories (cal)
• It is also known as the large calorie.
One kilocalorie is defined as the amount of heat required to raise the temperature of 1 kilogram of
water by 1°C.
/ M.Sc Exam-Oriented Notes)
Course:
B.Sc / M.Sc Nutrition & Dietetics
Subject:
Nutritional Biochemistry / Human Nutrition
Unit:
Basics of Energy Metabolism, Nutrition & Dietetics
Contents Covered
• Units of measurement of energy
• Calorific value of food
• Basal Metabolic Rate (BMR)
• Factors affecting BMR
• Specific Dynamic Action (SDA) of food
• Calculation of energy requirement
• Balanced diet
• Nutrition in health and disease
• Protein Energy Malnutrition (PEM)
Type of Notes
Exam-Oriented | Simple Language | Concept-Based
Suitable for:
B.Sc & M.Sc Nutrition / Clinical Nutrition / Dietetics Students
Prepared for academic learning and examination reference.
, NUTRITIONAL BIOCHEMISTRY
Basics of Energy Metabolism
1. Energy and Its Measurement
Meaning of Energy
Energy is defined as the capacity of the body to do work. All vital functions of the human body require
energy for their proper functioning. These functions include breathing, circulation of blood, digestion
and absorption of food, physical activity, maintenance of body temperature, growth, repair of tissues,
and overall metabolism.
The body obtains energy mainly from macronutrients present in food, namely carbohydrates, proteins,
and fats. Without adequate energy intake, normal body functions cannot be maintained.
Units of Measurement of Energy
Energy can be measured in different units. In nutrition and dietetics, the commonly used units are
calorie, kilocalorie, and joule.
1. Calorie (cal)
The calorie (cal) is the smallest unit of energy. It is defined as the amount of heat required to raise the
temperature of 1 gram of water by 1°C.
Because this unit is very small, it is not practical for expressing the daily energy needs of the human
body. Therefore, it is rarely used in nutrition.
2. Kilocalorie (kcal)
The kilocalorie (kcal) is the most commonly used unit of energy in nutrition.
• 1 kilocalorie (kcal) = 1000 calories (cal)
• It is also known as the large calorie.
One kilocalorie is defined as the amount of heat required to raise the temperature of 1 kilogram of
water by 1°C.
