Summa Technologiae

[Denis85]

Кстати, по поводу дефицита витамина D, может пояснит кто.
Вот, на сайте ВОЗ пишут, что это маловероятный дефицит.
WHO | The known health effects of UV
But 5 to 15 minutes of casual sun exposure of hands, face and arms two to three times a week during the summer months is sufficient to keep your vitamin D levels high. Closer to the equator, where UV levels are higher, even shorter periods of exposure suffice.
Hence, for most people, vitamin D deficiency is unlikely.