Gastric Cancer Dietary Therapy
After hospital confirmation of diagnosis, it is essential to seize the opportunity for surgery, especially for early-stage gastric cancer, which yields better outcomes; postoperative 3-year survival rate is 97.8%, 5-year survival rate is 90.9%, and 10-year survival rate is 61.9%.
In 1981, a report indicated that the 5-year survival rate for early gastric cancer reached 98%; more recent reports show a 100% 5-year survival rate for micro-gastric cancer. Therefore, early diagnosis and surgery are key to improving the cure rate of gastric cancer.
How to achieve early detection? Anyone over 40 years old without prior history of gastric disease who develops early gastrointestinal symptoms, or those with long-standing ulcer history showing significant changes or altered pain patterns, must not dismiss these as ordinary conditions but should undergo thorough examination. For individuals with precancerous lesions such as reduced gastric acid, gastric ulcers, atrophic gastritis, or gastric polyps, regular check-ups and early treatment are crucial. Recent improvements in early detection rates are mainly due to advances in diagnostic techniques; currently, electronic endoscopy is used, characterized by thinner diameter, wide-angle forward viewing, high resolution, and high clarity.
Recently, ultrasonic endoscopy has emerged, capable of assessing the depth of gastric cancer invasion and even detecting lymph node metastases outside the stomach. Surgical treatment remains the most effective approach for early gastric cancer, mostly using radical resection. After gastrectomy, some patients cannot maintain their original body weight due to trauma or inability to eat normally, leading to consumption of proteins, fats, and other nutrients, resulting in weight loss. Additionally, vitamin deficiencies and post-surgical complications may occur.
After gastrectomy, fasting is typically required initially. If general condition is good, bowel movements resume, and anal gas passage occurs within 24–48 hours, small amounts of warm water or glucose drinks can be given. If no discomfort arises, the next day light clear liquids such as rice porridge, vegetable soup, diluted lotus root powder, or weak fruit juice may be introduced, avoiding sucrose, milk, and soy milk as they may cause bloating. On day four, liquid diet continues, with addition of sweetened milk or sweetened soy milk. On day five, low-residue semi-liquid foods may be introduced, such as rice porridge, minced meat stewed with tomato juice and tofu, wontons, tomato or vegetable juice mixed with noodles, bread, cakes, milk, soy milk, etc. By day nine, switch to a nutritious, easily digestible, non-irritating, soft-textured diet consumed five times daily. If nausea or abdominal distension occurs after eating, reduce or stop intake. Resume feeding only after symptoms subside and condition improves.
Postoperative dietary recovery is crucial: it must compensate for chronic depletion caused by preoperative illness and repair surgical trauma. Thus, a five-meal-per-day regimen for gastric conditions should be maintained for a prolonged period, ensuring adequate nutrition, high protein, high vitamins, and sufficient vitamin A, B, and C intake to promote wound healing. Include eggs, dairy products and derivatives, lean meats, tofu, soy products, fresh tender vegetables, and ripe fruits. Avoid spicy and hard-to-digest foods such as chili peppers, celery, alcohol, coffee, strong tea, and high-fiber vegetables like celery and leeks.
Cooking methods also require attention—avoid frying, pan-frying, smoking, or raw salads, which hinder digestion. Use steaming, boiling, stewing, or braising instead. Patients should gradually transition back to normal diet only after full recovery from surgical trauma and physical weakness. Due to reduced stomach volume after gastrectomy, nutrient absorption is impaired; thus, increase intake of vitamin D-rich foods such as animal livers and carrots to prevent postoperative osteomalacia. Also, avoid immediate activity after meals; rest lying down, and avoid high-sugar diets to prevent dumping syndrome.
The most common complications after gastrectomy are iron-deficiency anemia and vitamin B complex deficiency. About 15% of patients develop osteomalacia due to vitamin D deficiency, making already thin bones prone to change. Even in patients without obvious vitamin D deficiency, early bone tissue changes can be corrected. It remains unclear whether post-gastrectomy osteoporosis and osteomalacia are related to vitamin D deficiency or calcium absorption issues. Nevertheless, these patients clearly exhibit impaired calcium absorption and vitamin D deficiency. Therefore, patients after gastrectomy should ensure adequate dietary calcium and vitamin D intake, which benefits bone calcification. Animal products such as egg yolks and liver contain high levels of retinol. Some plant-based foods like yellow and red vegetables and fruits contain β-carotene, which converts to vitamin A in the liver.
Calcium-rich foods include various bean products, dairy items, oatmeal, cabbage, Chinese cabbage, carrots, celery, pumpkin, radishes, spinach, gourds, leeks, dandelions, winter melon, etc. Certain nuts and seeds are also high in calcium, such as dry apricots, walnuts, hazelnuts, sunflower seeds, etc. Fruits like oranges are also rich in calcium.
Vegetables such as spinach, amaranth, and water spinach contain oxalates that impair calcium absorption. To reduce oxalate content, blanch these vegetables briefly in boiling water, discard the water, then stir-fry. When preparing flour, cornmeal, or bean flour, add fermentation agents and extend fermentation time to hydrolyze phytic acid, releasing free calcium and enhancing calcium absorption.
When resuming food intake after surgery, start with a six-meal-per-day regimen for post-gastrointestinal surgery, then transition to a five-meal-per-day gastric diet as condition improves.
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