Major gastric resection alters digestive function and may lead to profound weight loss. The objective of our study was to evaluate trends in body weight loss after curative gastrectomy for malignancy. A review of patients who underwent gastrectomy from 1999 to 2012 at two institutions was conducted. Patient demographics and treatment were assessed. Student's t test and analysis of variance were used to compare groups. Of 168 patients, two patients (1.2%) were Stage 0, 73 (43.5%) Stage I, 46 (27.4%) Stage II, 45 (26.8%) Stage III, and two (1.2%) stage unknown. Fifty-eight patients (34.5%) underwent total gastrectomy with Roux-en-Y esophagojejunostomy and 110 patients (65.5%) underwent subtotal gastrectomy. The average per cent decreases in body mass index (BMI) postgastrectomy at one month, six months, 12 months, and 24 months were 7.6, 11.7, 11.5, and 11.1 per cent, respectively (P = 0.003). The decreases in BMI were the same for all time periods whether patients had subtotal or total gastrectomy. Weight loss after gastric cancer resection is an important measure of quality of life. By understanding patterns of weight change after gastrectomy, we can better counsel and prepare our patients for the long-term effects of gastric cancer surgery.