You’ve probably heard the expression, “We are what we eat,” but we could just as easily say, “We are how we sleep.”

It’s common knowledge that a lack of sleep can affect our bodies, leaving us with less energy to do all the things we want to do. But we also think that somehow being able to get by with fewer hours of sleep is a sign of strength or toughness. Science is now showing us that when a lack of sleep affects our bodies, it also impacts our ability to think clearly, regulate our emotions, control our bodies and enjoy life.

Researchers are learning more about the connection between healthy sleep and our physical and mental health and well-being. A lack of sleep can increase the risk of developing obesity, high blood pressure, Type 2 diabetes, stroke, coronary heart disease and depression. 

Why sleep?

During sleep, the body forms and maintains the pathways in your brain that let you learn and create new memories, and make sure you’re able to concentrate and respond quickly when you are awake. During sleep, your body physically rests and rebuilds itself from the work of the day, while your brain rewires itself and performs tasks, like precisely regulating your hormones. A lack of sleep disrupts that balance, and sleep-deprived people have higher levels of stress hormones and substances in their blood. This can lead to an increased risk for heart attack, stroke and other diseases of the vascular system. 

Studies also show that sleep-deprived people are more likely to gain excess weight. This may be due to eating more, especially high-fat foods and snacks. A lack of sleep can disrupt the reward systems in your brain, including those that regulate judgment and food preferences, making you more impulsive and likely to make bad choices. Sleep-deprived people may feel too tired to exercise, putting them at additional risk. Once a person becomes overweight or obese, they have an increased risk of developing a sleep disorder such as sleep apnea or insomnia, which further reduces sleep quality and quantity.

The risks of sleeping too little

People who sleep poorly due to insomnia — or have difficulty falling or staying asleep — may remain in a state of heightened alertness and anxiety due to the brain’s inability to get the sleep it needs to function well. This can lead to high blood pressure, which increases risk for stroke, heart attack and other health problems.

The good news is that we can all resolve to get better quality sleep. Just like better hand hygiene keeps us from getting a cold, better sleep improves not just how we feel each day, but the health of our hearts and ultimately our brains. Sleep health is an important part of brain health.