Explaining stretch marks
Stretch marks, or striae as they are called medically, are simply scars that appear in the dermis, rather than on the epidermis, like conventional scarring from outside injuries. Stretch marks are formed when the skin is stretched beyond its limits in order to accommodate a sudden increase in body size-because of pregnancy, body building, or weight gain, for example—which creates small tears in the skin. Stretch marks can also occur because of hormonal changes (the kind that come with pregnancy and puberty as well as from external agents like hormone replacement therapy and steroidal drugs). Although they can pop up almost anywhere, stretch marks are most likely to occur in areas where the body stores its extra fat, such as the belly, breasts, hips and thighs (an exception to this rule would be in body builders, who typically get stretch marks in the skin around the bigger muscles, like the biceps). When they’re newly formed, stretch marks look red and shiny, but after a few months will turn a whitish color and often become slightly indented or depressed. While they do become less noticeable over time, once they’re formed, stretch marks are almost always here to stay.