We aimed to ascertain the implementation of body composition assessment, by means of fat-free mass index (FFMI), fat mass index (FMI) and presence of sarcopenic obesity, in colorectal cancer population, on the basis of hospital length of stay (LOS) determination and to benchmark their discriminatory performance with other nutrition status algorithms, such as body mass index (BMI) and Malnutrition Universal Screening Tool (MUST). Ninety adult patients with operable colorectal cancer were enrolled. Study parameters included demographic and anthropometric data registration, BMI and MUST calculation and body composition parameters measurement within 24-h post-admission. Hospital LOS constituted the outcome of interest, using 7 days as cut-off point. Fifty-one patients (56.7%) were hospitalised for ≤7 days. The presence of sarcopenic obesity affected adversely hospital LOS (OR, 9.236; 95% CI, 3.278-26.173, P = 0.000). Low FFMI (OR, 7.457; 95% CI, 2.868-19.390, P = 0.000), malnutrition according to MUST (OR, 2.632; 95% CI, 1.280-5.413, P = 0.009) and high FMI (2.133; 95% CI, 1.111-4.094, P = 0.023) were the most powerful discriminators of accelerated hospitalisation. Loss of lean body tissue, gain of adipose tissue and sarcopenic obesity confer noteworthy prognostic value being superior or equivalent to MUST in terms of hospital LOS determination in colorectal cancer resection setting. BMI presents inferior discrimination performance in this field.