From the Guidelines
Refeeding causes constipation primarily due to changes in gut motility and digestive function after a period of reduced food intake. When someone begins eating again after fasting or malnutrition, the digestive system needs time to readjust. The intestines may have slowed their movement during the period of reduced intake, and suddenly introducing food can overwhelm this sluggish system. Additionally, refeeding often involves increased caloric intake without sufficient fiber or fluids, which are essential for proper bowel movements. The body also prioritizes nutrient absorption during refeeding, potentially extracting more water from stool and making it harder to pass.
Key Factors Contributing to Constipation
- Changes in gut motility
- Insufficient fiber and fluid intake
- Prioritization of nutrient absorption over bowel movement To prevent or manage refeeding-related constipation, the following strategies can be employed:
- Gradually increase food intake rather than returning immediately to normal portions
- Ensure adequate hydration with 2-3 liters of water daily
- Incorporate fiber-rich foods like fruits, vegetables, and whole grains
- Maintain physical activity as tolerated In severe cases, a mild osmotic laxative like Miralax (polyethylene glycol) at a dose of 17g daily mixed in water may help temporarily, but addressing the underlying dietary and hydration factors is most important for long-term resolution, as suggested by recent guidelines on nutrition in cancer patients 1. The management of constipation in patients with severe chronic small intestinal dysmotility also supports the use of fiber-rich foods, adequate fluids, and osmotic laxatives like polyethylene glycol 1.
From the Research
Refeeding Syndrome and Constipation
There is no direct evidence in the provided studies that refeeding causes constipation. However, the studies discuss the refeeding syndrome, which is a potentially lethal complication of refeeding in patients who are severely malnourished.
Key Features of Refeeding Syndrome
- The refeeding syndrome is characterized by severe electrolyte disturbances, particularly low serum concentrations of phosphate, magnesium, and potassium 2, 3, 4, 5.
- It reflects the change from catabolic to anabolic metabolism 2.
- The syndrome can cause various metabolic and pathophysiological complications, affecting the cardiac, respiratory, hematological, hepatic, and neuromuscular systems 4.
Prevention and Treatment of Refeeding Syndrome
- Patients at risk of refeeding syndrome should undergo a risk assessment and stratification before starting nutritional therapy 6.
- Nutritional support should be administered with adapted energy and fluid support during the replenishment phase 6.
- Electrolyte disturbances should be aggressively corrected 5.
- Careful patient monitoring and multidiscipline nutrition team management may help to achieve the goal of preventing and treating refeeding syndrome 2.