Sleeping in a side-lying position that presses on the breasts is not the main cause of breast enlargement. Breast enlargement is an imbalance in the secretion of estrogen and progesterone in the body that leads to the incomplete restoration of the mammary glands and the eventual occurrence of hyperplasia. Sleeping in side-lying position will sometimes block the local blood circulation of the breast and easily produce pain symptoms, but judging from the mechanism of breast hyperplasia, as long as the endocrine imbalance in the body can be properly regulated, breast hyperplasia can be better controlled. Patients should develop good sleep habits, avoid staying up late and keep a relaxed mood, which can effectively balance the body’s endocrine problems and reduce the triggers of breast enlargement. In addition, dietary avoidance of spicy, stimulating food, should be light, low-salt, low-fat, low-fat food, are conducive to the prevention and alleviation of breast hyperplasia.