Background: Cancer cachexia is considered intractable, with few therapeutic options. Secondary nutrition impact symptoms (S-NIS) such as nausea may further contribute to weight loss by decreasing nutrient intake. In addition, treatable metabolic abnormalities such as hypogonadism, vitamin B12 deficiency, hypothyroidism, and hypoadrenalism could exacerbate anorexia and muscle wasting in patients with cancer cachexia. We determined the frequency and type of contributors to appetite and weight loss, and the effect of the cachexia clinic on clinical outcomes. Methods: Review of 151 consecutive patients referred to a cachexia clinic. All received dietary counseling and exercise recommendations. Assessments included weight, body mass index (BMI), S-NIS, resting energy expenditure by indirect calorimetry, serum thyroid stimulating hormone (TSH), cortisol, total testosterone, and vitamin B12. Results: Median weight loss in the 100 days before referral was 9% (4%-13%); median BMI at presentation was 20.8. Median number of S-NIS was 3 (2-4), most commonly treated by metoclopramide, laxatives, and antidepressants. Forty-one percent (24/59) of patients were hypermetabolic and 73% (52/71) of males hypogonadic, whereas hypoadrenalism (0/101, 0%), hypothyroidism (4/113, 4%), and low vitamin B12 (3/107, 3%) were uncommon. Poor appetite and weight loss before referral (r ¼ 0.18, p ¼ 0.036) were associated with increased S-NIS (r ¼ 0.22, p ¼ 0.008). Appetite improved ( p < 0.001) and 31/92 (34%) of patients returning for a second visit gained weight. Conclusions: Patients had a high frequency of multiple S-NIS, hypogonadism, and hypermetabolism. A combination of simple pharmacological and nonpharmacological interventions improved appetite significantly, and increased weight in one third of patients who were able to return for follow-up. Cachexia clinics are feasible and effective for many patients with advanced cancer.