What are the dietary adjustments after surgery for rectal cancer?

In general, dietary management after surgery for rectal cancer should follow several key principles: a gradual dietary transition, adequate intake of high-quality protein, moderate supplementation of dietary fiber, strict avoidance of irritating foods, and eating small, frequent meals. A detailed explanation is as follows:

1. Gradual Dietary Transition

During the first 1 to 3 days after surgery, patients should begin with a liquid diet, such as rice water and lotus root starch. After bowel movements resume and there is no abdominal distension, patients can gradually transition to semi-liquid foods, such as congee and steamed egg custard. Around one week post-surgery, soft foods such as well-cooked noodles and tofu can be introduced. During this process, solid or difficult-to-digest foods should be avoided early to reduce the burden on the intestines and lower the risk of obstruction.

2. Ensure Adequate Intake of High-Quality Protein

After surgery, the body requires sufficient protein to repair tissues. Easily digestible, high-quality protein sources such as steamed fish, tender chicken, eggs, tofu, and yogurt are recommended. The daily recommended intake should be calculated at 0.8–1.2 g/kg of body weight, which can enhance immunity and reduce muscle loss.

3. Moderate Supplementation of Dietary Fiber

Dietary fiber can be gradually increased during the recovery period, such as softened spinach, pumpkin, yam, and apple puree, which help promote intestinal motility and prevent constipation. However, coarse fiber sources such as celery, leeks, or undercooked vegetables should be avoided, as they may irritate the intestines or cause bloating.

4. Strict Avoidance of Irritating Foods

Because the intestines are sensitive after surgery, spicy, fried, raw or cold foods, and gas-producing foods such as legumes, onions, and carbonated beverages should be avoided. These foods may cause intestinal spasms, bloating, or diarrhea, which can delay the recovery of bowel function.

5. Eat Small, Frequent Meals

Due to the reduced intestinal capacity after surgery, it is recommended to eat 5–6 meals per day, each to about 70–80 percent fullness, to avoid overloading the intestines with a single large meal. At the same time, daily water intake should be maintained at 1500–2000 ml to prevent dehydration and constipation.

The specific dietary plan should be adjusted according to the type of surgery and individual recovery status. It is recommended that patients develop a personalized meal plan under the guidance of a dietitian or attending physician to promote intestinal function recovery and reduce the risk of recurrence.