WARNING!
This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.
Catching a quick nap midday may be a simple, no-cost way to lower your blood pressure, according to researchers from the Asklepieion General Hospital in Voula, Greece.1
The research, presented at the American College of Cardiology’s 68th Annual Scientific Session, suggests midday sleep could be as effective at slashing blood pressure levels as other lifestyle interventions, like reducing alcohol intake or taking low-dose blood pressure medication.
It's unclear whether the results vary depending on whether a person is sleep-deprived or typically gets a good night's sleep, but it could be that a nap may be particularly useful for people lacking in high-quality sleep.
High blood pressure affects more than 1.13 billion people worldwide,2 including 1 in 3 U.S. adults. Another 1 in 3 have prehypertension, but many are unaware that their health is at risk from this "silent killer."3
Fortunately, beyond napping there are other powerful strategies to lower your blood pressure as well, such as improving nitric oxide levels, which I’ll discuss later. But first, it does appear that for some people a nap a day may help keep high blood pressure away.
Napping May Lower Your Blood Pressure Levels
The study followed more than 200 people with high blood pressure, monitoring their blood pressure levels, midday sleep time, lifestyle habits and pulse wave velocity, which is a measure of arterial stiffness.
Those who napped had an average systolic 24-hour blood pressure reading that was 5.3 mm Hg lower than those who did not, while both blood pressure numbers were also more favorable among nappers compared to non-nappers. It appeared that, for each hour of napping, 24-hour systolic blood pressure was lowered by 3 mm Hg.
"We obviously don't want to encourage people to sleep for hours on end during the day, but on the other hand, they shouldn’t feel guilty if they can take a short nap, given the potential health benefits,” Dr. Manolis Kallistratos told the American College of Cardiology (ACC). “Even though both groups were receiving the same number of medications and blood pressure was well controlled, there was still a significant decrease in blood pressure among those who slept during midday."4
The study may be a good representation of napping benefits, as those included in the study had well-controlled blood pressure. Whereas those with high, uncontrolled blood pressure levels may have more pronounced drops from interventions, by using a group with controlled levels "we can feel more confident that any significant differences in blood pressure readings are likely due to napping," Kallistratos said.5
The study also monitored the natural dips in blood pressure that occur during sleep, finding that the natural drops were similar across the participants. This suggests the reductions noted in the study could be due to the napping intervention. Kallistratos told ACC:6
"These findings are important because a drop in blood pressure as small as 2 mm Hg can reduce the risk of cardiovascular events such as heart attack by up to 10 percent. Based on our findings, if someone has the luxury to take a nap during the day, it may also have benefits for high blood pressure. Napping can be easily adopted and typically doesn't cost anything."
Napping May Improve Function, Thinking and Memory
Aside from lowering blood pressure, taking naps offers other health benefits, including to people over 60 years, who typically have shorter periods of deep sleep and more frequent waking at night. Taken together, older adults may sleep for nearly two hours less on average than young adults.
It used to be believed that older adults didn't need as much sleep, but now it's thought that most people thrive on seven to eight hours of sleep a night. When researchers started a napping regimen among men aged 50 to 88, it turned out that midday sleep helped the men significantly increase their sleep over a 24-hour period, leading to enhanced cognitive performance.7
What's more, the naps — even up to two hours a day — did not negatively affect the men's nighttime sleep, but the researchers suggested one-hour naps may be easier for most people to accommodate. Napping has also been shown to facilitate memory consolidation and learning and support emotional processing.8
Napping Isn't Always a Good Thing
Paradoxically, there's also some research showing napping is associated with negative outcomes, even including an increased risk of high blood pressure,9 and the following, especially in older adults:10
While it’s unlikely that naps are directly causing these health problems, the association exists nonetheless, and more research is needed to determine who benefits from naps, who doesn’t and why. “An emerging hypothesis,” researchers wrote in Sleep Medicine, “suggests inflammation is a mediator between midday naps and poor health outcomes, yet further research is necessary."11
It’s also been suggested that the length of the nap may make all the difference, with those less than 30 minutes promoting wakefulness and enhanced performance and learning ability, and those longer being associated with health problems, including higher mortality in the elderly.
"The benefits of napping could be best obtained by training the body and mind to awaken after a short nap," according to researchers in the journal Current Opinion in Pulmonary Medicine.12
The Most Profound Way to Lower Your Blood Pressure
While the jury's still out on whether naps are ultimately beneficial or harmful, it's quite clear that improving your nitric oxide (NO) is the most profound thing you can do to lower your blood pressure because it relaxes your blood vessels.
NO is a soluble gas stored in the lining of your blood vessels, called the endothelium. NO is produced inside your endothelial cells from the amino acid L-arginine, where it acts as an important signaling molecule throughout your body.
Along with promoting healthy endothelial function and heart health, NO supports healthy blood flow by helping your veins and arteries dilate. This, in turn, allows vital oxygen and nutrients to flow freely throughout your body — beneficial for your circulation and brain health.
NO also improves your immune function, stimulates the thinning of your blood and decreases blood viscosity, which in turn decreases platelet aggregation — ultimately reducing your risk of developing a life-threatening blood clot.
Callisthenic exercises, such as the Nitric Oxide Dump, can help increase NO production. It involves just four movements — squats, alternating arm raises, non-jumping jacks and shoulder presses — which are done in repetitions of 10, with four sets each.
The workout takes just three or four minutes and should be repeated three times a day, with a minimum of two hours between sessions. I typically do a modified version of the one developed by Dr. Zach Bush, which you can view below. In addition, a comprehensive exercise program is essential to keep your blood pressure levels healthy.
Research shows inactive individuals have a 30 to 50 percent greater risk for high blood pressure than their active counterparts, and "An evidence based literature analysis by the American College of Sports Medicine indicates that an isolated exercise session (acute effect) lowers BP [blood pressure] an average of 5-7 mmHg."13
Using Your Diet to Improve Blood Pressure
Leafy greens and beets are important dietary components if you have high blood pressure, as they're good sources of naturally occurring nitrates that are converted into NO in your body. Because beets are high in sugar, fermented beet juice, also known as beet kvass, may be a far preferable option, as virtually all of the sugar is eliminated during the fermentation process.
I often include about 1 to 2 ounces of raw beets in my daily smoothie, in addition to taking a fermented beet root powder supplement. Eating garlic may also help, as although it’s low in nitrates, it helps boost NO production by increasing nitric oxide synthase (NOS), which converts L-arginine to NO in the presence of cofactors such as vitamins B2 and B3.14
Fennel seeds are another healthy food that increases your body's production of NO. Potassium also works in your body to relax the walls of your arteries, keep your muscles from cramping and lower your blood pressure.15 An analysis of over 29 trials demonstrated low levels of potassium resulted in higher systolic blood pressure readings.16 Leafy greens and avocado are examples of potassium-rich foods.
On a larger scale, however, high blood pressure is often the result of too much insulin and leptin in response to a high-carbohydrate and processed food diet. A cyclical ketogenic, low net-carb, high-fat diet is the solution, as it will allow your body to burn fat rather than glucose as its primary fuel. Fasting is a natural partner to a ketogenic diet and is one of the most effective ways to normalize your insulin/leptin sensitivity.
In one three-month study, the participants were allowed to eat whatever they wanted in any quantity between 10 a.m. and 6 p.m. For the remaining 16 hours, they were only permitted water or calorie-free drinks.
The outcomes were then compared to a nonintervention control group from a previous fasting trial. Overall, participants not only consumed about 350 fewer calories per day and lost just under 3 percent of their body weight, but systolic blood pressure also dropped about 7 mmHg.17
Healthy Lifestyle Is the Secret to Optimal Blood Pressure
Your blood pressure is one of many biological functions affected by your lifestyle, and leading a healthy one is the key to keeping your level in the optimal range. Sleep is definitely part of this equation, and for some people it may be that napping helps them to increase their sleep and results in overall health benefits.
A strong link between sleep quality and a type of high blood pressure known as resistant hypertension, which does not respond to typical drug-based treatments, has previously been found, for instance.18
Women who had resistant hypertension were five times as likely to also have poor sleep quality. While the average length of sleep in this study was only 6.4 hours a night (and nearly half slept fewer than six hours each night), it was sleep quality, not quantity, that appeared to influence hypertension risk.
So, getting a good night’s sleep is essential to healthy blood pressure, but so is eating right, exercising, addressing stress and even avoiding environmental toxins, like air pollution. For more details, you can find more information to normalize high blood pressure here.