The purpose of this investigation was to evaluate in a randomised crossover study the effects on nutritional status of two isonitrogenous-isocaloric regimens of total parenteral nutrition (TPN) in 12 severely cachectic cancer patients. The regimens consisted of (1) G: 50 kcal of glucose.kg(-1).day(-1) + 2g amino-acids.kg(-1).day(-1) (2) GL: 30 kcal glucose and 20 kcal lipids.kg(-1) + 2g amino-acids.kg(-1).day(-1). Regimens G and GL were delivered sequentially for a period of 10 days each. Six patients (Group A) were randomised to receive regimen G first and regimen GL subsequently. In Group B patients the regimens alternated in the opposite way. The following nutritional variables were measured before TPN, after regimen G and after regimen GL: weight, arm circumference, arm muscle circumference, triceps skin fold, serum proteins, serum albumin, cholinesterase, transferrin, pre-albumin, retinol-binding protein, peripheral lymphocytes, cumulative nitrogen balance and mean urinary excretion of creatinine and 3-methylhistidine. The data showed that body weight and retinol-binding protein significantly increased with both G and GL regimens. No difference was found in the remaining variables, not even when comparing regimen G to GL. Increase in retinol-binding protein and in nitrogen balance were significantly better in the first period of treatment than in the second. These results show that the two regimens had a similar impact on the nutritional status of the cachectic cancer patients and choice between a glucose or a glucose-fat TPN should depend mainly on tolerance of the patients, duration and cost of therapy.