The role of Vitamin D in skin cancer patients

Sunlight, especially its ultraviolet B (UV-B) rays, plays a complex role in human health. On one hand, it can be harmful—UV-B exposure is known to damage DNA in skin cells, which can lead to mutations and, over time, increase the risk of skin cancer. This connection is supported by the high number of UV-related genetic mutations commonly found in different types of skin tumors. On the other hand, UV-B is also essential for something our bodies can’t do without: producing vitamin D. When our skin is exposed to sunlight, UV-B triggers a chemical reaction that starts with the conversion of 7-dehydrocholesterol into previtamin D₃. Through a series of metabolic steps, this becomes active vitamin D—a compound that has shown promising anti-cancer properties in lab studies. For example, vitamin D can help prompt cancer cells to self-destruct, slow down their uncontrolled growth, prevent the development of new blood vessels that feed tumors, and encourage normal skin cell development. Interestingly, for people already diagnosed with skin cancer, having enough vitamin D might offer certain advantages. Some research suggests that maintaining adequate vitamin D levels could help slow the progression of the disease and potentially improve treatment outcomes. So while it’s important to protect the skin from excessive sun exposure, it’s equally important not to overlook the health benefits of moderate UV-B exposure and particularly its crucial role in vitamin D synthesis and its possible protective effects against cancer.