Stretch marks are caused when middle layer of your skin, also known as dermis, stretches. The dermis layer of the skin is made up of strong fibres that allow your skin to stretch as your body grows. However, if the growth occurs rapidly over a short period of time, these fibres are over-stretched and begin to tear. As the dermis begin to break, blood vessels underneath the skin start becoming visible. Hence, stretch marks start out as red and purple in appearance. Over the time when the blood vessels contract and the fat under your skin starts showing, stretch marks fade to become silvery white in colour.
Although stretch marks are mainly caused by stretching of the skin, some people are more prone to developing them than others. Here are some factors that can either cause or make developing stretch marks more likely:
- Weight gain and muscle growth
It has been seen that people who have higher levels of cortisol in their body are more likely to develop stretch marks. Cortisol is responsible for decreasing the amount of collagen, a protein that makes skin elastic. Decreased collagen level in the skin, makes it vulnerable to tears and hence increasing chances of marks.
Pregnancy is a most common cause of stretch marks in women. Around 90% of women start developing these marks after the sixth month of pregnancy. Rapid weight gain and expansion of the skin around tummy due to baby growth is mainly responsible for the marks. Hormones produced during pregnancy that soften the ligaments in pelvis to make delivery easy, also make the skin fibres thin, making them prone to tearing.
Growth spurts and hormonal changes during puberty are the leading cause of stretch marks among teens. During puberty, body grows at a pace more than that can be handled by the elasticity of the skin. This is a reason most teenagers notice marks on their shoulders, back, hips, breasts and thighs.
Rapid weight gain can cause skin to stretch excessively, leaving stretch marks. This is a reason why bodybuilders and athletes have marks on their body. Stretch marks caused by weight gain tend to remain even after you lose weight.
If you have a family history of stretch marks then you are more vulnerable to develop them yourself. So, if you want to know if you will get them, check whether your parents or grandparents had them. If you are genetically programmed to get marks, even taking prevention can’t help, though it can definitely help reduce the appearance of the marks
No matter what is the cause of your marks, there are treatments that can help reduce stretch marks.