No Burn, No Slim

Did you know that even when you are at rest, your body still burns calories? Not as much as when you are active of course, but still, there is some in-body activity going on that relies on energy. Even breathing needs energy! Resting Energy Expenditure or REE is the amount of energy needed when we are at rest. It represents the calories required by your body during a non-active period. Your REE is influenced by age, sex, body weight, pregnancy, and hormonal status.

As you age, your metabolism slows down. The highest rate of energy expenditure per unit of body weight occurs during infancy and childhood but declines through adulthood.

For example, in your 20s, you may find that you can eat much and not gain much weight. But in your 50s, you may find it difficult to shed those extra pounds even when you eat less than before.

As a child, in-body activities work round the clock. There is a lot of energy that is going on inside a child’s body. The energy is being produced because the child is growing. But as the child grows older, they need more REE due to body physiology.

In adult life, the decline continues at approximately two per cent every 10 years because of a decline in lean body mass.

There is a significant relationship between energy expenditure and fat-free mass, body surface area, and body weight.

It is also interesting to note that females have a lower energy expenditure per unit of weight than males, because generally, females have a higher proportion of body fat.

Pregnancy increases energy expenditure to support fetal growth and the increase in maternal tissues.

Several hormones, including thyroxin, catecholamines, and insulin, also increase energy expenditure. Those who are obese also have a higher REE than those with normal weight.