Naps Good for the Heart

Zoomer | March 2nd, 2007

A regular siesta reduces the chance of heart-related death by nearly 40 per cent among adults.

If you enjoy naps, here’s another reason to take them. A large study conducted by the Harvard School of Public Health (HSPH) and the University of Athens Medical School (UAMS) in Greece suggests that taking naps is actually good for your heart.

Siestas (defined by the researchers as midday naps longer than 30 minutes, more than three times a week) are common in Mediterranean and Latin American countries – where rates of heart disease are also lower.

The research team led by Androniki Naska, lecturer of hygiene and epidemiology in UAMS, and Dimitrios Trichopoulos, professor of cancer prevention and epidemiology at HSPH, set out to examine the question of whether the two might be linked, and how. The study looked at more than 23,000 individuals living in Greece. At the beginning of the study participants had no history of coronary heart disease, stroke or cancer.

The study participants were followed for an average of 6.3 years. The results: men who occasionally napped had a 12 per cent lower rate of death related to coronary heart disease. And men who napped close to daily had a surprising 37 per cent lower rate of death. Women were not affected at the same rates.

Other links between sleep and heart disease
The link between sleep and heart disease has been on the research agenda for several years. In 2003, a study at Brigham and Women’s Hospital in Boston found that women who are chronically sleep deprived seriously increase their risk of developing heart disease. That study looked at over 71,000 women between 40 and 65 years of age over ten years. Women who reported sleeping five hours or less per night were 45 per cent more likely to have heart problems.

However, that study also found that women who slept more than 9 hours a night were 38 per cent more likely to experience heart problems as well. This may be because individuals who need to sleep longer suffer from other conditions that impact on health, such as sleep apnea, or it may be that those individuals are less physically active, which also impacts on heart disease.

Stressed out? Sleep on it
One of the suspects in the link between lack of sleep and heart disease is stress. Stress hormones, particularly cortisol, are released into the body at higher rates when a person is sleep deprived. This may lead to problems with blood pressure and blood sugar regulation.

The HSPH and UAMS study may also demonstrate a link between stress, sleep, and heart disease. Further analysis of the results of the study showed that naps had a higher impact on the heart health of working men than it did on non-working men. This can be interpreted as pointing to a link to the role of sleep in regulating stress and its effects on the body – although not necessarily a complicated one.

“We know there are all sorts of physiological phenomena associated with sleep,” says Trichopoulos, in a Healthday news article. “But because sleep is such an important factor for cardiac mortality, it might have a simple stress-relieving impact.”

The final verdict? If you enjoy naps, take them. But be sure to get plenty of exercise, look for ways to reduce stress, and eat right as well.

According to the Heart and Stroke Foundation, cardiovascular disease accounts for the death of more Canadians than any other disease. In 2002, 32 per cent of all male deaths and 34 per cent of all female deaths in Canada were due to heart diseases, diseases of the blood vessels and stroke.