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Why can lighter skin be helpful for vitamin D production at high latitudes?

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Homo sapiens Human beings (Homo sapiens) are anatomically similar and related to the great apes but are distinguished by a more highly developed brain and a resultant capacity for articulate speech and abstract reasoning.

Lighter skin is helpful for vitamin D production at high latitudes because it allows for greater penetration of ultraviolet radiation through the epidermis.12

In the human body, vitamin D is synthesized when ultraviolet light triggers the photoactivation of 7-dehydrocholesterol present in the skin. Melanin, the pigment responsible for skin color, acts as a natural shield that absorbs ultraviolet radiation and limits its penetration into deeper skin tissues.13245

At high latitudes, where sunlight is less intense and exposure to ultraviolet rays is limited, the presence of high levels of melanin can hinder the skin's ability to produce sufficient vitamin D. By having less melanin, individuals with lighter skin allow more of the limited available ultraviolet light to penetrate the skin, thereby facilitating the necessary synthesis of vitamin D, which is essential for calcium metabolism and bone health.1342