What is refeeding syndrome and in which populations is it a risk?

• A. A benign shift in fluids after reintroduction.
• B. Increased appetite after refeeding.
• C. Low blood sugar after feeding.
• D. A dangerous shift in fluids and electrolytes (especially phosphate) after reintroducing nutrition to severely malnourished individuals; risk in people with prolonged starvation or severe malnutrition.

Answer: (D)

Refeeding syndrome is a dangerous shift in fluids and electrolytes that can occur when nutrition is reintroduced after a period of undernutrition. The key mechanism is a surge of insulin as carbohydrates are fed, which drives phosphate, potassium, magnesium, and fluids back into cells. This can cause severe hypophosphatemia and other electrolyte disturbances, leading to edema, heart rhythm problems, respiratory failure, weakness, and potentially death if not detected and managed.

The risk is highest in people who have had prolonged starvation or severe malnutrition, such as individuals with advanced anorexia or cachexia, and it can also occur in those with chronic conditions that cause long-standing inadequate intake. Because of this risk, refeeding must be approached cautiously with careful electrolyte and fluid monitoring and appropriate supplementation.