Obesity can increase water loss through skin, resulting in dry, dehydrated skin. Dry skin cracks increase the risk of infection.
Stretch marks are also common. Using moisturizing lotions such as Dermal Therapy Extra Strength Body Lotion keeps the skin soft reducing the appearance of stretch marks.
News-Medical Obesity & Skin Problems: http://www.news-medical.net/health/Obesity-and-skin-problems.aspx