How many calories/day should I consume?
I am sure this is a question that all of us have been wondering sometimes. There is not such an exact answer that it would magically work for everyone but, generally speaking, within a healthy and balanced diet, men needs around 10,500kJ (~2,500kcal) a day to maintain a healthy weight, and for women, this figure goes around 8,400kJ (~2,000kcal) a day. However, these values vary depending on age, metabolism and levels of physical activity, among other things.
Calories measure how much energy any food or drink contains. The amount of energy you need depends on: 1) age, for example, children and teenagers usually may need more energy because of their lifestyle; 2) activity level, how active are you at your size?; 3) height and weight can affect how quickly you use energy; and 4) other factors, such as hormone production, can affect how much energy you burn as well.
Calories vs kilocalories
Calorie is commonly used as shorthand for kilocalorie (kcal). Kilojoules (kJ) are the equivalent of kilocalories according to the International System Unit. You will see both kJ and kcal on nutrition labels, for example, 4.2kJ ~= 1kcal.
To maintain a healthy weight, you need to balance the amount of calories you consume through diet with the amount of calories you burn through physical activity.
If you're underweight, your body mass index is less than 18.5, it is highly recommended that you gain weight. To gain weight, you need to eat more calories than your body uses each day. Need guidance to gain weight safely?