While melasma is primarily associated with hormonal factors and sun exposure, some studies have explored the link between melasma and vitamin B12 deficiency. These studies suggest that there is a correlation between low levels of vitamin B12 and the development of melasma. Vitamin B12 deficiency is known to have various effects on the body, so it’s likely that in some cases, it can contribute to skin pigmentation changes as seen in melasma. Hormonal fluctuations, such as those that occur during pregnancy or while taking hormonal supplements, can trigger or worsen melasma. This is why melasma is sometimes referred to as "the mask of pregnancy." Additionally, exposure to UV radiation from the sun or tanning beds stimulates the production of melanin, which is the pigment responsible for skin color, leading to the presence of dark patches.