March 8-14 is Sleep Awareness Week, the perfect time to ask why our bodies need to switch off and recharge so regularly.

You’ll see sleep very differently after discovering all the good deeds a good night’s rest does...

1. Sleep conserves energy

The energy conservation theory is largely based on our metabolism, which research suggests is significantly reduced while we sleep – by as much as 10%. If we were to stay awake at night our ancestors would have faced a much more difficult time capturing their prey and next meal, using much more energy than necessary. Regularly switching off conserves our energy so that finding our next supply becomes an easier task.

2. Sleep restores cells

During our waking hours we damage cells in a number of ways, from the food and drink we consume to the physical activity we undertake. Sleep allows us to repair these cells to perform a number of basic bodily functions. While asleep, our damaged muscles and tissues repair, cuts heal, cells produce proteins and hormones are released.

3. Sleep reorganises our brain

The idea that we sleep to aid brain function is often referred to as the brain plasticity theory. Our brain’s waste clearance or glymphatic system clears toxic by-products from the central nervous system to improve performance when we wake up. A number of brain functions are impacted by our sleep, including memory, creativity, learning and problem-solving skills.

4. Sleep strengthens our immune system

Cytokines are proteins that fight infection and inflammation. Our body produces them as we sleep, along with antibodies and other immunity boosting cells. They’re one of many reasons why a good night’s sleep is vital when we feel unwell. As well as fighting off biological threats to our health, sleep assists with our emotional well-being. Brain activity in areas that regulate our feelings increases as we rest.

5. Sleep supports heart health

A lack of sleep is associated with a number of risk factors for heart disease, including an increase in our hunger hormone ghrelin which may lead to weight gain. Diabetes, also linked to heart disease, is more likely to occur when we regularly fail to get enough sleep. Sleep deprivation can also lead to high blood pressure and increased inflammation, both of which increase your chances of developing a cardiovascular condition.