Well there is nothing like all skinny people have stretch marks. Even those who gain weight suddenly get stretch marks. Stretch marks are scars or injuries on the skin which is caused by degeneration of the outer layer of the skin. read more
When the elastin in your skin is damaged, a stretch mark is in turn created. One cause of Stretch marks is "hormones". When we gain and lose weight it affects the hormones in our body, and also the hormones in our skin. read more