To determine whether the hair lines on the body are growth lines or obesity lines is mainly based on the body changes as well as weight and other factors to analyze. 1. Growth lines: also known as expansion lines, is due to the body’s bones, muscles and fat growth rate is too fast, more than the growth rate of the skin, resulting in the skin dermis of the elastic fibers fracture, so as to form a kind of lines on the surface of the skin, mainly in the limbs of the extensor side. From the point of view of body changes, height and weight will appear obvious changes. 2. Obesity lines: due to the accumulation of fat caused by skin elastic fiber fracture and lead to a kind of lines, which mainly occurs in the buttocks, chest, waist and abdomen, as well as the inner thighs and other fat-rich parts of the body from the point of view of the body changes, the main manifestation of weight gain. There is a certain similarity between growth lines and obesity lines, and the specifics need to be analyzed by a doctor in conjunction with the physical changes.