White streaks on the buttocks are considered to be atrophic lines. Atrophic lines may be caused by sudden weight gain or weight loss, being in pregnancy, long-term use of corticosteroid hormone drugs and other reasons. 1. Suddenly gain weight or lose weight: If the recent overeating, excessive weight loss, rapid increase in body fat or thin, may lead to skin elastic fiber rupture, so that the buttocks, abdomen, waist and other locations of the atrophic lines, similar to the appearance of white stripes. 2. is in pregnancy: women in pregnancy, weight gain is too fast, will also form atrophy lines. The color of the stripes is usually reddish when they are first formed, and will gradually turn to white. 3. Long-term use of corticosteroid hormone drugs: long-term use of such drugs will inhibit the function of fibroblasts, decomposition of elastin, resulting in elastic fiber degeneration, inducing atrophy lines. Generally speaking, atrophic lines will not affect the health of the body, without treatment, if it affects the aesthetics, you can go to the hospital to follow the doctor’s instructions for treatment.