Ultraviolet radiation is the most biologically active part of the solar spectrum.
UV rays are short wavelength compared to visible light and are divided into three classes: UVA (315-400nm), UVB (280-315nm), UVC (100-280nm) . In addition to giving our skin a beautiful hue, UV radiation is very important for the synthesis of vitamin D.
Find out at estet-portal.com about a new clinical study whose main goal was − effect of sunscreen use on vitamin D synthesis.
UV spectra are essential for the synthesis of vitamin D
The most life-threatening UVC rays do not reach the Earth's surface due to the ozone layer of the atmosphere. The ratio and power of UVA and UVB rays usually fluctuate and depend on many factors, in particular on daily and seasonal changes, the degree of air pollution, geographic latitude and the intensity of light reflection.
Follow us on Instagram!
It is known that UVB rays are a necessary condition for the synthesis of vitamin D by epidermal cells. At the same time, this spectrum of solar radiation rays is the main cause of the development of burns and skin cancer.
Seasonal care: treatment to prepare the skin for summer
Using sunscreen − a well-known recommendation that allows you to reduce the negative effects of sunlight, but at the same time can help reduce the physiological processes of calciferol metabolism in the human body.
Methodology for conducting a sunscreen study
During the observation by the researchers, a comparative analysis of the effectiveness of the use of two sunscreens with an identical level of sun protection factor in each of them (SPF 15) was carried out. However, the UVA protection factor (UVA-PF) was lower in one of the creams compared to the other.
The effect of sunscreen on vitamin D status was studied during a week of study participants' stay in Tenerife (28°N). Healthy volunteers (n = 20) were asked to use sunscreen during the holidays and the rules for their use were explained. In addition, comparison of performance with a control group (n = 17) and with a randomly selected sunscreen group (n = 22).
To assess the synthesis of vitamin D in the body, the level of 25-hydroxycalciferol (25 (OH) D3) in the blood serum was determined.
The results of the study showed an identical level of influence of the evaluated sunscreens (p = 0.599), the use of each of which was effective in preventing sunburn. In the study group with a randomly selected sunscreen, an increase in calciferol levels (p = 9 x 108) was observed with values of 28.0 ± mn; 16.5 nmol/l.
Stop photoaging: effective sun protection for face and body
Among volunteers who used low and high UVA-PF sunscreens, there was a statistically significant increase in serum vitamin D levels - (p≤6.7×10-5) 19.0 ± 14.2 and 13.0 ± 11.4 nmol/L 25(OH)D3 respectively. In the control group of observation, there was a decrease (p = 0.08) by 2.5 ± mn; 5.6 nmol/l 25 (OH) D3.
The results of the influence of sunscreens on the synthesis of vitamin D
In a new study by researchers at King's College London, UK, the hypothesis of impaired vitamin D synthesis associated with the use of sunscreens was refuted. In an article published in the British Journal of Dermatology, 2019, the authors of the study reported that during a week of cloudless weather with a fairly high index of ultraviolet exposure, even with the use of sunscreen to prevent sunburn, the study participants recorded an increase in vitamin D synthesis.
The new generation of UV filters in the field of aesthetic medicine
Practical implications for the use of sunscreens
Thus, based on the data obtained, the study authors concluded that sunscreens can be used to prevent sunburn, while not interfering with the necessary synthesis of vitamin D in the body.
The best sun protection: how to hide from UV radiation
However, the researchers noted that the use of sunscreens with a high level of UVA-PF protection provided more intensive calciferol synthesis compared to an analogue with lower preventive indicators. According to scientists, this fact is due to the high transmission capacity for ultraviolet rays of the UVB spectrum.
What gifts the sun gives us: the double effect of the sun on the body
Share:
Add a comment