Sleep duration has a direct impact on bone health. It actually seems possible to significantly reduce your personal risk of osteoporosis and the general risk of fractures through sufficient sleep.
As part of the University of Colorado School of Medicine's annual research day, faculty member Dr. Christine Swanson presented her clinical research into whether adequate sleep can help prevent osteoporosis.
Possible causes of osteoporosis
The causes of osteoporosis are varied. The doctor cites hormonal changes, aging and various lifestyle factors as examples. But there are also people for whom there is no apparent explanation for the development of osteoporosis.
This makes it clear how important it is to find possible previously unidentified risk factors for osteoporosis. Changes over the course of the life of those affected should also be taken into account, such as in sleeping habits, says Dr. Swanson.
Bone density decreases with age
In their early to mid-20s, most people reach what is known as peak bone density, which, according to the doctor, is generally higher in men than in women. After reaching this maximum, a person's bone density remains more or less stable for several decades.
When women reach menopause, bone loss begins at an accelerated rate. But it's not just women who are affected; men's bone density also decreases with age, explains Swanson.
Changes in sleep behavior in old age
Not only does bone density change over the course of life, but so does sleep. For example, the total duration of sleep decreases and the quality of sleep also changes, explains the expert.
“Circadian phase preference also changes over the course of life in both men and women,” adds Dr. Swanson added in a press release. Circadian phase preference describes the times when we prefer to go to sleep and when we wake up.
Circadian rhythm affects sleep and bones
The genes that control our internal clock are found in all bone cells. “When these cells reabsorb and form bone, they release certain substances into the blood that allow us to estimate how much bone turnover is occurring at a given time,” explains Dr. Swanson.
These markers for bone loss and growth follow a daily rhythm. According to the expert, the amplitude of this rhythm is greater for bone loss markers than for bone formation markers.
“This rhythm is likely important for normal bone metabolism and suggests that sleep and circadian disruption may directly influence bone health,” explains Dr. Swanson.
Effects of sleep disorders examined
To better understand this connection, the experts examined how markers of bone turnover respond to cumulative sleep disturbances and circadian rhythm disturbances in a fully controlled inpatient environment. The time of day was unclear to the participants and they were assigned to a 28-hour day instead of a 24-hour day.
The disruptions to the circadian system should simulate the effects that occur in people who work rotating night shifts, the team explains. Such a disruption would be roughly equivalent to a daily flight across four western time zones over a period of three weeks.
Another effect was that the participants got less sleep, explains Dr. Swanson. The researchers also measured bone turnover markers at the beginning and end of the intervention. It was shown that bone turnover changed significantly negatively in both men and women in response to the disturbed sleep and daily rhythm.
Bone loss, osteoporosis and increased risk of fractures
Poor sleep led to a decrease in bone formation markers. Regardless of gender, this decline was significantly greater among younger people than among older people, reports the expert. There was also a significant increase in bone loss markers in young women.
When people build less bone but the same amount (or even more) is reabsorbed, it can lead to bone loss, osteoporosis, and an increased risk of fractures, adds Dr. Swanson added.
“Gender and age can also play an important role, with younger women perhaps being most vulnerable to the detrimental effects of poor sleep on bone health,” said the doctor.
To protect your bones, make sure you get enough sleep
The current results are consistent with an earlier study published in the Journal of Bone and Mineral Research, which found negative effects of lack of sleep on bone health, particularly in postmenopausal women.
In summary, sleep plays a very important role in bone health and especially in protection against fractures, which seems to be particularly true for women. In general, you should always ensure that you get enough healthy sleep so that your bones remain healthy and resilient for as long as possible, even as you get older. (as)
