Even though the dangers of prolonged exposure to ultraviolet light are widely known, moderate sun exposure is essential for the synthesis of vitamin D in the body. Vitamin D is known to help relieve bone density and muscle mass loss, especially in the elderly. Although vitamins can usually be supplemented by taking them, sunbathing is most effective when it comes to naturally produced by the body.
Study Figure 1 – Effects of Ultraviolet Radiation on Skin Tissue (from: Nagoya University)
When the season shifts to the long night and the day is short, it is difficult for people living at high latitudes to get enough sunlight in winter. For older people with reduced mobility, it is less likely to sunbathe outdoors for long periods of time.
The good news is that UV LEDs (black flashlights) can be a good complement, even if there isn’t enough sun. It also avoids health problems caused by overdosing, such as premature skin aging or cancer.
It is reported that a team of researchers from Nagoya University first tested mice for the minimum dose and intensity of UV exposure required to synthesize vitamin D.
A controlled experiment was then conducted in mice with older genetic conditions (another group was not exposed to ultraviolet light) at twice a week.
Study Figure 2 – Before and after indicator pairing (from: Nature)
After 12 weeks, higher vitamin D levels were detected in the serum of mice treated with UV LED therapy, and bone density, muscle mass, and strength improved. What’s more, its skin is not damaged.
The team is now developing a portable UV LED device for older people designed to prevent or treat problems related to osteoporosis and muscle mass decline.
Lead scientist Yoshihiro Nishida said: “With this device, all older people can get the same or more vitamin D as sunbathing in a simple, safe and low-cost way.”
Details of the study have been published in the recently published journal Scientific Reports.
Originally titled “Low energy irradiation of narrow-range UV-LED prevents osteosarcopenia associated with vitamin D de ddie in senescence-accelerated mouse mouse resein 6.”