We all know that a good night’s sleep can make us feel great — just how a night of tossing and turning makes us tired and irritable. But did you know that sleeping well is also an essential part of being healthy? Take a look at these seven reasons why sleep is so crucial for health.

1. Poor Sleep Can Cause Weight Gain
People who don’t sleep enough are more likely to be overweight or obese — so much so that short sleep duration is one of the strongest risk factors for being obese. In one study, adults who regularly slept for less than 5 hours per night had a 55% increased risk of obesity.

2. Good Sleepers Eat Less Food
A bad night’s sleep — even just one — can make you crave more unhealthy foods, especially those high in refined carbohydrates and sugar. This is because a lack of sleep disrupts satiety and fullness hormone signaling, causing you to have a bigger appetite.

3. Sleep Improves Productivity
Sleep is vital for brain function, improving productivity, mental recall, focus, cognitive skills, and memory.

4. Sleep Improves Mental Well-Being
Regularly sleeping 7 to 8 hours each night is linked to better mental health, as poor sleepers are more likely to develop depression or anxiety.

5. Sleep Improves Athletic Performance
Similar to how sleeping can benefit mental and cognitive performance, it can also help athletes of any level improve their speed, accuracy, and reaction times. In older adults, less sleep is linked to slower walking speed, lower grip strength, and greater difficulty performing activities.

6. Good Sleepers Have Better Heart Health
Sleep duration and quality play a vital role in cardiovascular health. Those who don’t get enough sleep are at a significantly greater risk of developing heart disease or stroke than those who sleep 7 to 8 hours per night.

7. Sleep Improves Immunity
Lastly, healthy sleep durations will strengthen the immune system, leading good sleepers to become sick less often than poor sleepers.