How many days of sunbathing on the back are effective?
Dec 23, 2024
Source: Cainiu Health
Dr. Liu Wenmin
Introduction
In general, sunbathing the back may require 15 to 60 days to show effects. If an individual has a mild vitamin D deficiency and receives sun exposure during suitable seasons and times of day, 20-30 minutes of daily sunbathing on the back typically allows vitamin D levels in the body to begin rising within 15-30 days. This occurs because 7-dehydrocholesterol in the skin is converted into vitamin D under ultraviolet light.
Generally, it may take 15 to 60 days of sunbathing to achieve noticeable effects. Detailed analysis is as follows:
If an individual has a mild vitamin D deficiency and sunbathes during suitable seasons and times for 20–30 minutes daily, vitamin D levels in the body usually begin to rise within 15–30 days, as 7-dehydrocholesterol in the skin converts to vitamin D under ultraviolet light.
However, for individuals with severe vitamin D deficiency, such as the elderly or those who work indoors long-term with little outdoor activity, even with 30–60 minutes of daily sun exposure, it may still take one to two months to achieve a significant improvement in vitamin D levels, due to very low body reserves and possibly impaired regulatory mechanisms.
Sunbathing is a simple and effective health-promoting practice that can also relieve stress and improve sleep. Daily sun exposure may stimulate the brain to secrete serotonin, thereby initially alleviating mood and improving sleep. At the same time, care should be taken to protect the eyes and skin during sunbathing, avoiding damage caused by prolonged direct exposure to sunlight.
