New research offers further evidence of a link between lack of sleep and reduced levels of bone formation.
In a study published in the Journal of Bone and Mineral Research, getting too little sleep was linked with a higher risk of having low bone mineral density (BMD) and developing osteoporosis.
Researchers based the study on a sample of 11,084 postmenopausal women from the Women's Health Initiative (WHI). Those who reported sleeping five hours or less per night had lower BMD at all four sites assessed -- whole body, total hip, neck and spine -- compared with women who reported sleeping seven hours per night. After adjustments, women reporting five hours or less per night had 22% and 63% higher risks of experiencing low bone mass and osteoporosis of the hip, respectively. Similar results were seen with the spine.
"Our study suggests that sleep may negatively impact bone health, adding to the list of the negative health impacts of poor sleep. I hope that it can also serve as a reminder to strive for the recommended seven or more hours of sleep per night for our physical and mental health," commented lead author Heather Ochs-Balcom, PhD, of the University at Buffalo.
Two years ago, a separate study published in the Journal of Clinical Endocrinology and Metabolism showed that insufficient sleep may be an unrecognised risk factor for bone loss.
This study involved 10 healthy men undergoing cumulative sleep restriction and circadian disruption -- similar to that seen in jet lag or shift work -- in a lab. After three weeks, the participants had reduced levels of a marker of bone formation in their blood, while a biological marker of bone resorption, or breakdown, was unchanged.
"This altered bone balance creates a potential bone loss window that could lead to osteoporosis and bone fractures," explained lead investigator Dr Christine Swanson, an assistant professor at the University of Colorado.