Numerous studies have addressed how inadequate sleep affects our bodies. The medical community has linked it to metabolic disorders, depression, and even diseases such as cancer. But a new study shows that it might also be tied to lower bone formation.
Researchers from the University of Colorado found that healthy men who didn’t achieve adequate amounts of sleep for three weeks had reduced levels of a marker of bone formation in their blood. This is dangerous, they say, because it opens the possibility of bone-related conditions whose causes have been partially unexplained.
"This altered bone balance creates a potential bone loss window that could lead to osteoporosis and bone fractures," said lead investigator Dr. Christine Swanson. "If chronic sleep disturbance is identified as a new risk factor for osteoporosis, it could help explain why there is no clear cause for osteoporosis in the approximately 50 percent of the estimated 54 million Americans with low bone mass or osteoporosis.”
Younger people affected most
The researchers analyzed 10 men and investigated the consequences that sleep deprivation and circadian disruption had on bone formation. Swanson described circadian disruption as “a mismatch between your internal body clock and the environment caused by living on a shorter or longer day than 24 hours."
Each subject stayed in a lab for three weeks and followed a sleep schedule wherein they went to bed four hours later than they did on the preceding day. Each person was allowed to sleep for 5.6 hours per 24-hour period, and the researchers controlled calorie intake and nutrition.
After three weeks, the researchers examined blood samples and measured them for bone biomarkers. They found that every participant had reduced levels of P1NP when compared to their baseline stats at the outset of the study period. The difference was greatest in participants aged 20-27, compared to those aged 55-65. Additionally, Swanson said that one marker called CTX remained constant throughout the period, indicating that old bone was breaking down but new bone was not being made.
"These data suggest that sleep disruption may be most detrimental to bone metabolism earlier in life, when bone growth and accrual are crucial for long-term skeletal health. Further studies are needed to confirm these findings and to explore if there are differences in women," she said.
The full study was presented at the Endocrine Society’s 99th annual meeting.