Sleep long and prosper. This take on the famous Star Trek mantra of Mr. Spock has its foundations in a ton of medical studies, which shows a good night’s sleep is essential for good health – especially heart health.

The U.S. National Institutes of Health (NIH) says the lack of adequate sleep (7 to 8 hours a night), also known as sleep deprivation, does have profound consequences on our physical health. Sleep deprivation places a person at risk of serious medical conditions such as heart disease, obesity, and diabetes. It also shortens ones’ life expectancy.

NIH said an occasional night without sleep makes a person feel tired and irritable the next day, but won't harm his health. On the other hand, after several sleepless nights, the mental effects become more serious.

The brain addles, making it difficult to concentrate and make decisions. The risk of injury and accidents at home, work and on the road increases.

To these obvious effects of sleep deprivation must now be added the much deeper but unseen effects it has on one’s heart at the cellular level. Research has consistently shown that sleeping for less than 6 hours per night rather than for 7 to 8 hours could increase a person's risk of atherosclerosis by as much as 27 percent. Atherosclerosis is a medical condition in which plaque builds up inside the arteries. If allowed to continue long enough, this plaque build-up will seriously restrict blood flow, causing a heart attack.

One of the newest studies in this regard explains how a good night’s sleep can help keep the arteries supple, thereby maintaining good circulation.

How a lack of sleep affects blood circulation by promoting the build-up of fatty deposits in the arteries (or atherogenesis), which can increase a person's risk of experiencing a stroke or heart attack, was tackled in a new study from the University of Colorado Boulder.

This study published in the journal Experimental Physiology pinpointed a potential biological mechanism explaining why this occurs. It links sleeplessness to changes in the blood levels of micro RNA (miRNA), which are noncoding molecules that help regulate protein expression.

"This study proposes a new potential mechanism through which sleep influences heart health and overall physiology,” said senior author Prof. Christopher DeSouza.

The study found that participants who slept for less than 7 hours a night had blood levels of three key circulating miRNAs (miR-125A, miR-126, and miR-146a) that were 40 percent to 60 percent lower than those of their peers who slept for 7 or 8 hours.

These three miRNAs suppress the expression of proinflammatory proteins. Low levels of these molecules are a problem because they are like cellular brakes. This means that if beneficial microRNAs are lacking, that can have a big impact on the health of the cell.

The study shows insufficient circulating miR-125A, miR-126, and miR-146a might lead to a host of vascular problems. These include inflammation; a higher risk of experiencing cardiovascular disease and related events such as a stroke or a heart attack.

The study also revealed that endothelial cells, which comprise the lining of blood vessels, in adult men who slept for less than 6 hours each night did not function properly.

As a result, the blood vessels of these men were unable to dilate and contract properly to allow blood to flow efficiently to different organs and parts of the body.

"Why 7 or 8 hours (of sleep per night seems to be the magic number (in maintaining health) is unclear," admits Prof. DeSouza.

"However, it is plausible that people need at least 7 hours of sleep per night to maintain levels of important physiological regulators, such as microRNAs."

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