The chemical substance is a nutrient
Well theres alot of ways that you can see if a person is dying like if a person's breathing patterns may also be irregular and the Changes in blood pressure, xtremities may feel cold to touch. Hallucinations, delirium, and agitation. An body temperature going up and down that would be another sign of death.
Hope it helps :)
Answer: Saturated fats
Explanation: When you eat food that contains high levels of saturated fats, your liver produces more cholesterol.