Stretch marks are a common skin condition that affects millions of people, regardless of age, gender, or ethnicity. They can be caused by a variety of factors, such as pregnancy, puberty, rapid weight gain or loss, and even certain medical conditions.
Stretch marks form when the skin stretches beyond its capacity to adjust to the change. This can happen due to rapid growth or weight gain, which causes the skin to tear and leave scars. Initially, stretch marks may appear as red or purple lines on the skin, but over time, they fade to a lighter color and become less noticeable.