Biology – 7.1 Human nutrition – diet | e-Consult

Starvation is a severe condition resulting from a prolonged lack of adequate food and nutrition. It has profound and cascading effects on the human body, impacting virtually all organ systems. The body prioritizes survival, leading to a series of physiological changes designed to conserve energy and maintain vital functions.

Initial Stages: In the initial stages, the body utilizes stored glycogen in the liver and muscles for energy. This provides a temporary energy reserve, typically lasting around 24-48 hours. As glycogen stores deplete, the body begins to break down fat for energy through a process called lipolysis. This releases fatty acids into the bloodstream.

Metabolic Changes: With limited carbohydrate and fat availability, the body shifts to using protein as a primary energy source. This is not ideal as protein is crucial for tissue maintenance and repair. Protein breakdown leads to muscle wasting and a decrease in immune function. The body also experiences a metabolic slowdown to conserve energy, resulting in a lowered basal metabolic rate. This can lead to a state of lethargy and reduced physical activity.

Organ System Effects:

• Digestive System: Reduced digestive activity due to lack of food. The digestive system becomes atrophied.
• Cardiovascular System: Decreased blood volume and reduced cardiac output. This can lead to hypotension (low blood pressure) and heart failure.
• Immune System: Suppressed immune function, making the individual highly susceptible to infections.
• Nervous System: Cognitive impairment, weakness, and difficulty concentrating. Neurological damage can occur in severe cases.
• Musculoskeletal System: Muscle wasting and weakness. Bone density can also decrease.

Long-Term Consequences: Prolonged starvation can lead to irreversible organ damage, chronic health problems, and even death. Recovery from severe starvation can be challenging, and individuals may experience long-term health complications.