In the last 100 years, we’ve lopped off almost 20% of our sleep time. Us Americans are the worst of all. Almost 1 out of every 2 American adults aren’t catching the recommended amount of Z’s a night. About 1 in 3 of us are trying to survive on 6 hours or less. Overall, our country’s average snooze time is just 6.5 hours.
What’s the big deal about fewer hours of sleep? We’re more productive for it, right? Plus, we’ll sleep when we’re dead.
In reality, we’ll actually be dead a lot sooner if we don’t sleep, and the quality of that now shorter life will be significantly worse. Let’s get the Debby Downer details around sleep deprivation over with quick. Then, we’ll talk about what you can do to hack your sleep and boost your health.
How bad can bad sleep really be? According to Matthew Walker—Professor or Neuroscience and Founder and Directer of the Center for Human Sleep Science—our life literally depends on longer sleep.
The shorter you sleep, the shorter you live. Inadequate sleep predicts an earlier death from any cause.
It’s time to wake up to the truth about poor sleep. Here are a few more frightening facts, according to Matthew Walker, for those of us who are stubbornly sleep-deprived:
Insufficient sleep across a lifespan is now recognized as one of the most significant lifestyle factors that determine whether or not you’ll develop Alzheimer’s disease. During sleep, your body cleanses your brain of toxins, including beta-amyloid—one of the leading causes of Alzheimer’s. The less you sleep, the more of that toxic amyloid builds up night after night.
After just one week on 6 hours of sleep, otherwise healthy adults experienced an erosion in the very fabric of their biological life—their DNA code. 711 of their genes were distorted as a result! About half of these genes were immunity genes, and these were switched off. The other half of the distorted genes were ones that promoted tumors, chronic inflammation, stress, and cardiovascular disease — these genes increased in activity.
Insufficient sleep is tightly linked to cancer of the bowel, prostate, and breast. The association is so powerful that, recently, the World Health Organization decided to classify any form of nighttime shift work as a probable carcinogen.
After 20 hours of being awake, you’re as impaired cognitively and physical as you would be legally drunk. Drowsy driving kills more people on the roads than either alcohol or drugs combined. In fact, for every 30 seconds you’ve been reading this, there’s been a car accident linked to sleeplessness.
Men who sleep 5-6 hours a night will have the level of testosterone equal to someone 10 years older. A lack of adequate sleep will age you by a decade in terms of fertility, muscle strength, and sexual performance.
The results are fast. We experience a remarkable state of immune deficiency after even just one night of poor sleep. One study found that after one 4-hour night of sleep, participants had a 70% reduction in critical anti-cancer fighting immune cells called “natural killer cells.”
Twice a year, scientists can observe a global experiment performed on 1.6 billion people across 70 countries. It’s called daylight savings time. In the spring, when we lose an hour of sleep, we see a subsequent 24% increase in heart attacks. In the fall, when we gain an hour of sleep, there’s a 21% decrease in heart attacks.
Could a lack of sleep be undermining your weight loss efforts? The science says, “Without a doubt!”
Two hormones control your appetite and weight: Leptin (the full and satisfied hormone) and Ghrelin (the hunger hormone). Even healthy people see a decrease in the full hormone, leptin, and a ramp-up in the hunger hormone, ghrelin, after 1 week on 4-5 hours of nightly sleep.
When we’ve underslept, we not only eat more, but we eat more of the wrong things. People who sleep 5-6 hours a night eat on average between 200-300 extra calories each day. This adds up to about 10-15 pounds of increased body fat each year. Sleep deprived people also eat more heavy-hitting carbohydrates, simple sugars, and processed foods and are low on intaking greens, nuts, and proteins.
With just 6 hours of sleep, your time to physical exhaustion drops by up to 30%. Lactic acid also builds up quicker in your muscles the less you sleep. Your peak muscle strength, vertical jump height, and running speed decreases with less sleep. Your lungs’ ability to expire carbon dioxide and inhale oxygen decreases too. Athletes who sleep only 5 hours have a 60% increase in probability of injury risk during a season.
Your body becomes stingy in giving up its fat when it’s sleep deprived. If you’re dieting and exercising but not getting sufficient sleep, 70% of all the weight that you lose will come from lean body mass (muscle and not fat), which means you end up looking less toned and retain more fat in exchange.
Sleep is the elixir of life. Its the most widely-available and powerful health boost for humanity. Sleep is:
So what’s the minimum amount of sleep you need each night to skip the bad news and reap the rewards?
The sweet sleep spot is 7-9 hours a night. Once we slip below seven hours of sleep, if you could peak through your scull and skin, you’d be able to measure objective impairments to your brain and body.
A lack of sleep actually impairs our ability to know how we’re doing objectively. In other words, when we’re sleep deprived, we’re terrible at recognizing that we are sleep deprived.
Thankfully, the scientists can give us an objective perspective. The number of people who can survive on 6 hours of sleep or less a night without showing any impairment is is 0% of the human population. Yup, you heard that right! A super small fraction (less than 1%) of humans have an incredibly rare gene that allows them to survive on about 5 hours of sleep a night without physical and mental consequences. The rest of us—we undeniably need 7-9 hours nightly.
Here are the 5 most powerful changes you can make to improve your sleep, according to a neuroscientist sleep specialist:
Now that you know the science of sleep, you may start to see that sleep is not the third pillar of good health alongside diet and exercise. It’s the foundation on which those two other pillars sit.
If you want to improve your health and boost your weight loss, start with sleep. Try out the five hacks listed above, and make sleep a priority in your health journey.