Does the amount of fat a person has affect whether or not something can penetrate their skin?

The amount of fat a person has under their skin, also known as subcutaneous fat, does not significantly affect whether or not something can penetrate the skin. Skin penetration primarily depends on the nature of the object and the force with which it's applied.

Human skin has several layers, with the outermost layer called the epidermis, followed by the dermis, and then the subcutaneous fat layer. The epidermis acts as a barrier to protect internal tissues from infection, dehydration, and physical harm. When an object is sharp and applied with sufficient force, it can penetrate through the epidermal and dermal layers to reach the subcutaneous fat.

The thickness of these skin layers can vary widely among individuals and different parts of the body. While a thicker layer of fat may provide a bit more cushioning against blunt force, it does not significantly change the protection against skin penetration by sharp objects. If an object is sharp enough and the force is great enough to get through the dermis, it will likely penetrate fat as well.