What are milia (fat bumps), what causes them, and why is it dangerous to try to squeeze them out of the house?

Milia are small, firm, white or yellowish cysts formed when dead skin cells and keratin accumulate in the upper layer of the skin and become trapped under the skin due to a clogged pore opening. Unlike pimples, they do not contain inflammation and do not have a central opening (pore opening). Attempting to squeeze them at home with a fingernail will not cause them to burst because they lack a pore opening; instead, it can crush the surrounding tissue, rupture capillaries, and lead to permanent pitted acne scars or infections. In a clinical setting, milia are painlessly removed in a single step by micro-puncture (using a lancet) with the tip of a sterile insulin needle.