The body can turn yellow after death primarily due to a buildup of pigments resulting from decomposition processes. One key factor is the accumulation of bilirubin, a yellow pigment formed from the breakdown of hemoglobin in red blood cells. After death, the body's organs stop functioning, enzymes begin breaking down tissues (autolysis), and bacteria proliferate, leading to putrefaction. Putrefaction produces chemicals like hydrogen sulfide, which react with hemoglobin to form pigments such as sulfhemoglobin that can stain the skin yellow-green. Additionally, if the person had liver failure before death, jaundice caused by bilirubin buildup can contribute to a yellowish color after death. Initially, the body may also undergo a pale yellow pallor mortis due to blood settling and cessation of circulation, but the yellow color typically develops as decomposition progresses over hours to days.
Key Reasons for Yellowing
- Bilirubin accumulation: Breakdown of red blood cells releases bilirubin, which has a yellow pigment.
- Decomposition pigments: Bacterial putrefaction produces hydrogen sulfide reacting with blood pigments to cause yellow-green discoloration.
- Jaundice (if present): Liver failure before death leads to jaundice, causing yellowing of the skin and eyes.
- Pallor mortis: Early pallor (paleness) includes yellowish tint as blood circulation stops and blood settles.
This yellow discoloration is part of the normal postmortem changes and becomes more evident as decomposition advances.
