What Is Melasma?
Who Gets Melasma?
Melasma is far more common than most people realize, affecting approximately five million people in North America alone:
- Women of reproductive age Roughly 90% of melasma cases occur in women, particularly between the ages of 20 and 50, with hormonal factors playing a major driving role.
- Individuals with medium to darker skin tones Those with Fitzpatrick skin types III–V (olive, brown, and dark complexions) are significantly more susceptible due to more active melanocyte responses.
- Pregnant women Often called the “mask of pregnancy,” melasma frequently appears during pregnancy as estrogen and progesterone levels surge, stimulating excess melanin production.
- People taking hormonal medications Oral contraceptives, hormone replacement therapy, and certain fertility treatments can initiate or intensify melasma in predisposed individuals.
- Those with a family history A strong genetic component has been documented, with studies showing that over 50% of melasma patients have at least one close relative with the same condition.
If melasma patches have appeared on your face and resist your current skincare efforts, professional assessment is the logical next step.
Common Causes of Melasma
- Ultraviolet radiation Sun exposure is the single most significant trigger for melasma, as UV rays stimulate melanocyte activity and darken existing patches rapidly, even through cloud cover and windows.
- Hormonal changes Elevated estrogen and progesterone levels during pregnancy, while using oral contraceptives, or during hormone therapy directly increase melanin synthesis in the skin.
- Heat exposure Infrared radiation and ambient heat from cooking, saunas, hot yoga, and even prolonged screen exposure can trigger melasma independently of UV light.
- Genetic predisposition Family history is one of the strongest predictors of melasma, indicating that inherited melanocyte sensitivity plays a foundational role in who develops the condition.
- Inflammation and skin irritation Post-inflammatory responses from harsh products, aggressive treatments, or skin injuries can stimulate pigment overproduction in melasma-prone skin.
- Thyroid dysfunction Emerging research has linked thyroid irregularities to melasma onset, suggesting that broader hormonal imbalances beyond reproductive hormones may contribute.