A nutritional assessment including determination of symptoms potentially influencing weight loss was prospectively performed on 254 consecutive cancer patients with favorable performance scores (Eastern Cooperative Oncology Group [ECOG] level 0 to 2). Primary cancer sites included the following: non-small cell lung (n = 93), colon (n = 50), prostate (n = 23), oropharyngeal (n = 18), breast (n = 15), gastrointestinal (n = 13), and other (n = 42). Thirty-nine percent of patients had received no prior chemotherapy or radiation therapy. Common symptoms in the population were abdominal fullness (61%), taste change (46%), constipation (41%), mouth dryness (40%), nausea (39%), and vomiting (27%). Current caloric intake was surprisingly similar in 170 patients with weight loss (percent usual body weight [PUBW], ≤95%) compared with 84 without weight loss (PUBW, >95%; 31.4 ± 1.5 versus 30.5 ± 2.1 kcal/kg/d, respectively). Symptoms identified by multivariate analysis as occurring significantly more frequently in populations with weight loss included abdominal fullness (P < 0.001), taste change (P < 0.002), vomiting (P < 0.005), and mouth dryness (P < 0.02). There was no difference in frequency of symptoms between patients with or without prior chemotherapy. These results indicate that gastrointestinal/oral symptoms potentially influencing weight loss are prevalent early in the course of cancer patients with unresectable disease, regardless of current nutritional status, caloric intake, or prior therapy experience.