We’ve seen our stress levels skyrocket as a society as we take on more at home and in the office. Our culture has answered this challenge by getting less sleep. Some think it’s a badge of honor. But trying to get through your life without enough rest (sleep macho) is nothing to be proud of. It’s quite simply very detrimental to your health. In fact, new research shows that getting less than seven or eight hours a night (as an adult) increases your risk of high blood pressure, along with a host of other problems such as encouraging weight gain.
A few months ago, researchers published the results of a unique study on the connection between a good night’s sleep and high blood pressure. This multi-year study, which was part of a larger study called CARDIA, followed 578 early-middle-aged adults. Previous studies that measured the effects of sleep, or lack of sleep, over multi-years relied on patient observations. However, this study used a specially designed wrist band that objectively measured the duration and quality of sleep.
Blood pressure was measured in 2000, 2001, 2005, and 2006. And in 2003 and 2005, subjects wore the wrist bands for three consecutive days, allowing researchers to gather more data. They found that when the subjects slept fewer than seven or eight hours and/or if their quality of sleep was poor, the subjects were more likely to have high blood pressure (both systolic and diastolic) at both the beginning of the study and five years later. In fact, each hour of sleep that a subject missed meant a 37 percent increase in the risk for high blood pressure. Knutson¹
This makes sense. Physiologically, anything that increases inflammation or contributes to chronic inflammation is going to negatively affect the cardiovascular system. Sleep is, hands down, the body’s most effective way of digesting excess stress hormones from your day. If you don’t get enough sleep, your stress hormones stay elevated and this increases inflammation throughout your body. This causes your arteries to narrow and even constrict, which results in higher blood pressure.
Not getting enough sleep has become an epidemic in our society. So has obesity. And these two are connected. Obese people are more likely to develop sleep apnea than their thinner counterparts. When you have sleep apnea, you don’t get enough sleep, and the quality of your sleep is often poor. Sleep apnea has been shown to obstruct the flow of oxygen to the body. And this condition has been connected to an increased risk of stroke, cardiovascular disease, and diabetes in obese people. Cappuccio²
The Rhythm of Life
On my radio show “Flourish,” I was recently interviewing Frank Lipman, M.D., author of the book Spent, about the fact that Thomas Edison and his light bulb invention might have done more to disrupt our health than anyone else. We now have the option of staying up all night because we can. Before this, we got up with the sun and went to sleep shortly after sundown. When Frank worked in the bush of South Africa, he said that he never saw people who were fatigued or “spent.” It simply didn’t happen. They lived according to the rhythms of nature.
One hundred years ago, we allowed our bodies’ need for sleep to be in line with the seasons. Like the animals, we were more active in the summer months and got a lot more rest in the winter. We are now coming up on the winter solstice, the darkest night of the year. What a great time to get in touch with your circadian rhythms!
One way to help readjust your inner clock is to take melatonin, a naturally occurring substance that promotes deep sleep. Another way to do this is to have what Dr. Lipman calls “an electronic sundown.” Turn off all TV’s, computers, and blackberries (and so forth) by 10:00 p.m. at the latest.
The health benefits of living in harmony with our body’s wisdom are too numerous to count. Sleep is a prime example. In addition to the benefits already mentioned, getting enough sleep has also been shown to help keep weight down. (Read Sleep Away Excess Pounds.) It also helps promote brain health and an upbeat mood. So sleep when you’re tired and don’t feel guilty. When I was at the California Women’s Conference in October, a reporter asked me what I’d do with an extra hour in my day. I quickly replied, “Take a nap.” I wasn’t kidding. Those extra hours of rest will benefit you for years to come.
- Knutson, K.L., et al. 2009, Association between sleep and blood pressure in midlife, The CARDIA Sleep Study, Arch Intern Med, 169:1055-1061.
- Cappuccio, F.P., et al. 2008. Meta-analysis of short sleep duration and obesity in children and adults, Sleep, May 1;31(5):619-26.