Sleep has numerous benefits, and research as well as the medical community, are showing several ways in which sleep can protect health.

Pain Reduction: According to Stuart Quan, MD, contributing editor to Harvard Health Publishing’s Harvard Health Blog, from Harvard Medical School, nearly 70 percent of Americans report getting insufficient sleep on a regular basis, and approximately 20 percent of Americans suffer from chronic pain.

The association between sleep deficiency/poor sleep and intensified pain perception has been widely studied; poor sleep quality predicts greater intensity of pain from conditions such as arthritis. Frequently, he said, the relationship is bi-directional. “For example, my colleagues and I have documented that heartburn is worse after a poor night’s sleep, and conversely heartburn can result in disrupted sleep,” he noted. “The relationship between poor quality sleep and worsening pain has important implications for individuals experiencing both acute and chronic pain. More or better sleep may lessen the pain that they are experiencing.”

Dr. Quan pointed to MRI brain scans showing that those individuals experiencing pain and poor sleep have higher activation of brain regions that control pain perception the day after a poor night’s sleep along with a reduction in the part of the brain that reduces pain sensation. “The net effect is that the perception of pain is accentuated after a poor or inadequate amount of sleep. Importantly, this observation is not just a phenomenon confined to the laboratory. In surveys of individuals with chronic pain, a night of poor sleep predicts worse pain,” he wrote.

Improved Immune Function: A good night’s sleep improves T cells’ ability to do their job of attaching to targets and eliminating them, according to a new study which helps explain how sleep can fend off an infection.

T cells are critical for effective immune response. When T cells recognize a specific target, such as a cell infected with a virus, they activate integrins (a protein) that allow the T cells to adhere to their target and, in the case of a virally infected cell, neutralize it. Although science has identified signals that activate integrins, researchers wanted to seek and identify signals that might impede the ability of T cells to attach to their targets are less well understood.

Adrenaline and prostaglandin levels decline during sleep. The researchers compared T cells taken from healthy volunteers while they slept or stayed awake all night. T cells taken from sleeping volunteers showed significantly higher levels of integrin activation than T cells taken from wakeful subjects. The researchers were able to confirm that the beneficial effect of sleep on T cell integrin activation was due to the decrease in Gαs-coupled receptor activation.

“Our findings show that sleep has the potential to enhance the efficiency of T cell responses, which is especially relevant in light of the high prevalence of sleep disorders and conditions characterized by impaired sleep, such as depression, chronic stress, aging, and shift work,” said study co-author Luciana Besedovsky.

Reducing Risk of CVD: Massachusetts General Hospital (MGH) researchers have discovered one way that sleep protects against the buildup of arterial plaques. In the new study, the team describes the mechanism by which insufficient sleep increases production of inflammatory white blood cells known to be major contributors to atherosclerosis.

“We have discovered that sleep helps to regulate the production in the bone marrow of inflammatory cells and the health of blood vessels and that, conversely, sleep disruption breaks down control of inflammatory cell production, leading to more inflammation and more heart disease,” stated Filip Swirski, PhD, of the MGH Center for Systems Biology, study senior author. “We also have identified how a hormone in the brain known to control wakefulness controls processes in the bone marrow and protects against cardiovascular disease.”

The researchers repeatedly interrupted sleep of mice genetically programmed to develop atherosclerosis. They found that the sleep-disrupted mice developed larger arterial plaques and had higher levels of monocytes and neutrophils—inflammatory cells that contribute to atherosclerosis—in their blood vessels compared to the group that slept soundly without interruption.

References:

Dimitrov, et al.. “Gαs-coupled receptor signaling and sleep regulate integrin activation of human antigen-specific T cells.” The Journal of Experimental Medicine, 2019; jem.20181169 DOI: 10.1084/jem.20181169

McAlpine CS, et al. “Sleep modulates haematopoiesis and protects against atherosclerosis.” Nature, 2019 DOI: 10.1038/s41586-019-0948-2

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