Texas Esthetician License Practice Exam

What stimulates melanin production?

1. Genetic factors

2. Exposure to sunlight

3. Aging

4. Pollution

The correct answer is: Exposure to sunlight

Exposure to sunlight is a significant factor that stimulates melanin production in the skin. When the skin is exposed to ultraviolet (UV) radiation from the sun, it triggers melanocytes, the cells responsible for producing melanin, to increase their activity. Melanin acts as a natural defense mechanism against UV radiation, helping to protect the skin from potential damage. This hormonal response results in the darkening of the skin, often referred to as tanning. While genetic factors, aging, and pollution can influence skin characteristics and health, they do not directly stimulate melanin production in the same way that sunlight does. Genetic factors determine baseline levels of melanin and skin type, aging can affect the overall function of skin and melanin production, and pollution can lead to skin damage or irritation but does not specifically trigger increased melanin synthesis. Therefore, the primary and most direct stimulator of melanin production among the options provided is exposure to sunlight.