Why is sleep so important to our health?
You probably know how it feels to wake up feeling unrested, and to wander through the day in that foggy, sleepy haze. If you haven’t felt it in a while, maybe you’ve got your sleep figured out (yay!), or maybe your body has gotten used to the feelings of lack of sleep and you don’t even realize that your energy levels, mood, and sharpness are lower than they could be. In our stressed-out, over-worked, success-focused society our sleep often gets pushed to the back-burner. Chances are, you’ve heard about the more surface-level effects of sleep deprivation: irritability, poorer memory, skin aging, etc. If you consider your health a priority, however, here are some of the key reasons sleep should be right up there on that list.
1. Cardiovascular health
A recent study investigating the relationship between sleep duration and cardiovascular disease compared those with short sleep durations (less than 6 hours) and long sleep durations (more than 8 hours) to a control group of people who get 6 to 8 hours a night. It was found that too little sleep increases your risk of developing or dying from coronary artery disease or stroke by 11%. Surprisingly, too much sleep was also associated with a 33% increased risk. It was also noted that “more research is needed to clarify exactly why, but we do know that sleep influences biological processes like glucose metabolism, blood pressure, and inflammation — all of which have an impact on cardiovascular disease.”
Another study conducted around the same time found “men with the shortest sleep duration at the age of 50 were twice as likely to have had a cardiovascular event by age 71 than those who slept a normal amount, even when other risk factors were taken into account.”
2. Diabetes
Studies have shown that not getting enough sleep can lead to eating more, exercising less, and therefore gaining weight — which is a risk factor for diabetes, in itself. However, studies have been conducted to find out whether sleep deprivation has a more direct link to diabetes. It turns out, your risk of developing Type 2 diabetes does increase with lack of sleep, even if you aren’t gaining weight. Sleep deprivation increases your risk for insulin resistance, and a study performed on mice found these changes were significant after only one 6-hour period of sleep deprivation.
3. Alzheimer’s
It has been shown that sleep deprivation is associated with β-amyloid pathology, which may contribute to cognitive decline in the elderly. Digging a little deeper, research has been conducted on the link between sleep deprivation and one of the risk factors of Alzheimer’s: excess amyloid-beta in the brain. In summary: “Sometimes, especially when cheated on sleep, the brain doesn’t get the chance to mop up all the A-beta that the neurons produce… If A-beta piles up too much, it can accumulate into plaques that are thought to eventually lead to other problems such as inflammation and the buildup of tau, which appears to destroy neurons and lead to Alzheimer’s disease.”
4. Inflammation
Sleep deprivation can prevent your cells from fighting inflammation, which has a host of health consequences. These include asthma, arthritis, multiple sclerosis, and even gastrointestinal disorders such as IBS and IBD.
One study even found that insufficient sleep alters gene expression in human blood cells, which might be the core explanation for a lot of these side-effects. What we didn’t touch on here are the ways that sleep impacts the other pillars of our health that we, typically, give more of a priority. In our next few posts in this series we will be going one-by-one through how sleep affects our nutrition, exercise, and mental health, and vice-versa, so be sure to follow along!
