What are stretch marks a result of?

Stretch marks, also known as striae, occur primarily due to the rapid stretching of the skin. This phenomenon typically happens during significant changes in body size, such as during pregnancy, puberty, rapid weight gain, or growth in muscle mass. The skin’s elastic fibers become overstretched and can break, leading to the formation of these marks. As the skin heals, the new tissue that forms may appear as lines that vary in color and texture.

In contrast, exposure to cold temperatures does not directly affect the elastic properties of the skin in a manner that leads to stretch marks. While excessive sun exposure can damage the skin and lead to other issues, it is not a direct cause of stretch marks. Similarly, inadequate hydration can lead to dry skin and other conditions, but it does not result in the rapid expansion of skin tissue that characterizes the formation of stretch marks. Therefore, the rapid stretching of the skin is the key factor in their development.