Our body requires energy for its metabolic and physiological functions. It gets its energy from food and its macronutrient constituents, that is, carbohydrates, fats, and proteins. Dietary energy intake from food must meet the requirements for achieving and maintaining optimal health, physiological function, and well-being.
Energy requirement is the amount of dietary energy needed to maintain body size, body composition, and a necessary level of physical activity consistent with long-term good health. Dietary energy requirements cannot be considered in isolation from other nutrients in the diet, as a lack of one will influence the others. Therefore, energy requirements must be met by consuming a diet that meets all nutrient needs.
Mitochondria are found in the cytoplasm of all eukaryotic cells, that is, cells with clearly defined nuclei. Its main function is to generate large amounts of energy in the form of adenosine triphosphate (ATP). The number of mitochondria per cell varies widely.
ATP, the energy carrier molecule, is found in the cells of all living things. When ATP is broken down, energy is released and can be harnessed for cellular work. Because ATP breaks down and reforms so easily, ATP is like a rechargeable battery that powers cellular processes.
ATP is often referred to as the “molecular unit of currency” of intracellular energy transfer. ATP captures the energy obtained from the breakdown of food and releases it to fuel cellular processes. Our body regenerates and recycles its own ATP-equivalent body weight each day.
Daily energy needs –
There are only small amounts of ATP in the body. Therefore, it is necessary to have sufficient energy reserves for backup. The amount of daily energy requirement depends on an individual’s daily energy intake and the metabolic energy requirement, which depends on the person’s body weight and activity level.
The energy we get from food to power our bodies is measured in kilojoules. Fats, carbohydrates, and proteins, found in food, provide energy.
The basic energy consumption of the human body is 4 kJ/kilogram of body weight per hour per day. So, the basic energy consumption of an individual can be calculated as follows:
Total energy consumption = Body weight (Kg) × 4 KJ × 24 hours/day / 4.18 kJ
The total value of energy consumption is divided by 4.18 kJ to convert the value to kilocalories (1 kcal = 4.18 kJ). This calculation represents daily energy consumption.
Individual energy requirements vary with age, gender, body size, and activity levels. Excess food intake that is not used for energy can be stored in the body as fat. Excessive fat storage can lead to a high body mass index (BMI).
BMI indicates a person’s body fat and is determined by a person’s height and weight. For adults, the suggested normal BMI is between 19 and 24. A high BMI can lead to illness or health complications. To have an ideal BMI, an individual’s energy intake should not exceed energy burned regularly.
Energy balance –
Energy balance is the relationship between the calories taken into the body through food and drink and the calories used by the body for our daily energy requirements.
When you eat more calories than you consume, you are in a positive energy balance. When you eat fewer calories than you consume, you are in negative energy balance. Your energy balance affects your metabolism, hormonal balance, and mood.
A negative energy balance leads to weight loss. The body detects an energy deficit and uses fat stores to make up the difference. A positive energy balance has its own ramifications not only in terms of weight gain but also in terms of health and fitness.
The conclusion –
The metabolic and physiological functions of our body require energy, which is produced from the food we eat. Mitochondria found in the cytoplasm of all eukaryotic cells generate large amounts of energy in the form of ATP. Our body generates its own equivalent body weight in ATP each day. Individual energy requirements vary with age, gender, body size, and activity levels.