As long as I wake up, no matter what time it is, by noon at 12:00 I also go out to sunbathe nude for about ten minutes. Especially sunbathing my back is important.

There is a 7-dehydrocholesterol in human skin that, after being irradiated by the sun’s medium-wave ultraviolet UVB, is converted into vitamin D3.
The core functions of vitamin D3: promoting the absorption of calcium and phosphorus in the intestines.
Boosting serotonin during the day, and making the nighttime release of melatonin more smooth.
After the sun’s warmth warms the back, it stimulates the back meridians, improving low back pain from sitting for long periods, cold body, and cold hands and feet, relaxing tense muscles.