Does the body enter a state of ketosis when dying?

Does the Body Enter Ketosis When Dying?

Yes, the body frequently enters ketosis during the dying process, particularly in cases involving starvation, malnutrition, severe illness, and certain metabolic crises, though the degree and significance varies by the underlying cause of death.

Ketosis in Different Death Processes

Starvation and Malnutrition

• Starvation-induced ketosis is a well-documented phenomenon at autopsy, where the body switches from carbohydrate to lipid energy sources as glucose becomes unavailable 1, 2.
• Forensic autopsy studies show that malnutrition and starvation cases demonstrate markedly elevated ketone levels in bilateral cardiac blood and pericardial fluid 1.
• The ketone elevation in starvation represents the body's adaptive metabolic response to preserve protein and utilize fat stores for energy 3, 4.
• Starvation ketoacidosis can be diagnosed postmortem even in embalmed bodies using vitreous humor testing, with sensitivity detecting acetoacetate levels as low as 10 mg/dL 5.

Critical Illness and Sepsis

• Ketone bodies are paradoxically suppressed in sepsis despite the metabolic stress, which may worsen outcomes 3.
• During severe bacterial infections, the absence of ketogenesis correlates with increased mortality, as ketone bodies normally protect against oxidative stress and reduce inflammation 3.
• The metabolic shift toward ketosis during critical illness represents an adaptive fasting response that can improve disease tolerance in certain contexts 3.

Thermal Stress

• Most cases of hyperthermia (heatstroke) and hypothermia (cold exposure) show increased ketones in cardiac blood and pericardial fluid at autopsy 1.
• This reflects the extreme metabolic stress and energy depletion occurring during thermal dysregulation leading to death 1.

Other Causes of Death

• Fatal alcohol abuse demonstrates elevated ketones similar to diabetic ketoacidosis, representing alcoholic ketoacidosis 1.
• Certain acute deaths including cerebrovascular disease and sudden cardiac death may show elevated blood glucose but variable ketone levels 1.
• Fatal methamphetamine abuse shows markedly lower blood glucose levels, suggesting different metabolic derangements 1.

Distinguishing Physiological from Pathological Ketosis

Physiological Ketosis Characteristics

• Normal pH, low but physiological insulin levels, and ketone bodies typically between 0.3-4 mmol/L 3, 4.
• This represents an adaptive metabolic state that occurs during fasting or carbohydrate restriction 3.

Pathological Ketoacidosis

• Characterized by low systemic pH, absent insulin, hyperglycemia, and very high ketone levels (>7-8 mmol/L) 3.
• Diabetic ketoacidosis cases show evidently high glucose levels at all body fluid sites including blood, pericardial fluid, cerebrospinal fluid, and vitreous humor 1.
• Nearly one-third of DKA deaths occur in individuals with no known history of diabetes, emphasizing the importance of postmortem ketone testing 6.

Forensic and Clinical Implications

Postmortem Detection

• Combined analysis of glucose, HbA1c, and ketones in blood and body fluids is essential to investigate not only diabetic metabolic disorders but also death processes from other causes 1.
• Vitreous humor is the preferred specimen for postmortem glucose and ketone analysis due to its relative protection from postmortem changes 1, 5.
• Volatile toxicology analysis should include acetone concentration, which when elevated together with elevated vitreous glucose indicates ketoacidosis 6.

Differential Diagnosis

• Starvation-induced hyperketonemia must be diagnosed per exclusionem after ruling out diabetic ketoacidosis, alcoholic ketoacidosis, and other causes 2.
• The levels of ketonemia in starvation ketoacidosis are usually mild compared to diabetic or alcoholic ketoacidosis 2.

Important Caveats

• Not all dying processes involve ketosis—acute traumatic deaths, certain poisonings, and rapid cardiovascular collapse may not allow time for metabolic shifts 1.
• The presence of ketones does not automatically indicate the cause of death but rather reflects the metabolic state during the dying process 2.
• Hyperketonemia itself can contribute to complications through oxidative stress and cellular damage, potentially accelerating the death process in vulnerable individuals 7.