How does embalming slow the decomposition of a body?

Embalming slows the decomposition of a body by introducing chemical agents that inhibit the natural processes of decay, primarily by sterilizing the remains and delaying putrefaction.1

In modern practice, this is achieved by draining blood from the veins and injecting a preservative solution—typically based on formaldehyde—into a major artery. Additionally, internal cavity fluids are removed and replaced with preservatives to further stabilize the tissues.2

These procedures counteract the biological breakdown that occurs after death, such as autolysis (the self-digestion of cells by enzymes) and the proliferation of bacteria that feed on bodily tissues. Historically, various methods were used to achieve similar ends, ranging from the use of spices, resins, and natron in ancient Egypt to the immersion of bodies in substances like vinegar, wine, or honey to "pickle" the remains. While these techniques are not permanent, they effectively preserve the body's appearance for a period following death, facilitating viewing during mourning rites.213