Which of the following is a common cause of skin thinning in elderly women?

The correct answer identifies decreased estrogen levels as a common cause of skin thinning in elderly women. As women age, particularly during and after menopause, there is a significant decline in estrogen production. This hormone plays a crucial role in maintaining skin health, primarily by supporting collagen production and skin hydration. With lower estrogen levels, the skin naturally loses its elasticity and moisture, leading to thinning and increased vulnerability to damage.

In contrast, excessive hydration generally enhances skin moisture and does not contribute to skin thinning. Adequate sun protection is essential to maintain skin health, as UV exposure can lead to various skin issues, including thinning, rather than being a cause itself. Chronic smoking is detrimental to skin health in multiple ways, such as reducing blood flow and increasing the risk of skin diseases, but it is not specifically linked to the hormonal changes that lead to thinner skin in elderly women. Therefore, the reduction in estrogen levels stands out as a key factor in the skin's aging process in this demographic.