Significant weight loss, especially in a short period, can lead to loose or excess skin. The amount of weight loss that causes loose skin varies from person to person, but generally, larger amounts of weight loss, such as 50 pounds or more, especially over a short period, can considerably increase the risk of loose skin. Factors such as age, genetics, and sun exposure can also play a role in the development of loose skin. Older skin with less collagen and elastin, as well as chronic sun exposure, can contribute to loose skin after weight loss. Additionally, individuals who have undergone weight loss surgery may experience more pronounced loose skin due to reduced collagen formation. Its important to note that loose skin is a common side effect of significant weight loss, and while there are ways to reduce the risk of developing loose skin, it is normal and usually wont cause any irritability. However, for some individuals, loose skin can affect their quality of life.