Leading a healthy lifestyle by combining a balanced and varied diet with regular exercise is key to reducing the risk of developing certain diseases such as cardiovascular disease, cancer and type II diabetes.
What is energy?
Energy is the power used to do work or provide heat. The chemical energy in our food is converted by the body into heat (thermal energy), and into movement (mechanical energy).
Our bodies need a constant supply of energy for maintaining body temperature, maintaining basic life processes, movement, growth and tissue repair.
Energy requirements
Energy is provided by macronutrients in the food we consume.
Each individual has different energy requirements, which vary depending on their size, weight, gender, level of physical activity, age and basal metabolic rate. Energy needs decrease as we get older, because muscle mass decreases and our overall level of activity reduces.
An average sedentary male's energy requirement is around 2500 kcal a day and for a woman the requirement is approximately 2000 kcal a day.
Energy balance
If we continually consume more energy from food and drink than we expend in the form of physical activity and other bodily functions, our body stores will increase leading to a positive energy balance. Continued over-consumption (energy intake higher than energy expenditure) will lead to weight gain and eventually lead to being overweight or obese.
Just like a pair of scales in equal balance, if energy from food and drink that we consume matches our energy expenditure then body weight will be maintained which is optimal for good health.
