Starting the first 24 hours after burn injury, energy supply, antioxidants and polyamines were assessed in 25 severe burn patients (20 men and 5 women) with a mean age of 45.6 +/- 20.4 years. Nutritional assessment was performed at 7, 15 and 21 days and was compared with a control group (n = 30). In 21 patients the burned body surface area was 20%-50% and in four patients it was greater than 50%. A mean decrease in energy supply of approximately 40% versus the calculated theoretical value was found in the three periods: 1,186 +/- 32; 1,117 +/- 589 and 1,331 +/- 578 kcal. In the first 15 days antioxidant ingestion was slightly lower than the recommended daily allowance for vitamin C: 60 mg versus 57 +/- 32, 57 +/- 53 and 75 +/- 53 mg, and was lower during the entire period for vitamin E: 10 mg versus 5.0 +/- 2.9; 4.5 +/- 3.0 and 5.3 +/- 3.4 mg; selenium: 40 microg versus 22.8 +/- 13.7; 22.5 +/- 9.8 and 25.7 +/- 11.2 microg and zinc: 12 mg versus 7.3 +/- 3.0, 6.8 +/- 4.8 and 8.4 +/- 5.3 mg. Taurine ingestion decreased on day 15 and significantly increased on day 21: 65.7 +/- 30 mg, 50.9 +/- 25 and 72.0 +/- 29 mg (p < 0.05). Ingestion of total polyamines did not differ significantly from the values observed in the control group and were as follows: day 7, total 45.2 +/- 23.0 umol, putrescine 16.7 +/- 10.2, spermidine 13.5 +/- 7.6 and spermine 13.6 +/- 8.8; day 15: total 41.1 +/- 38.5 and 14.9 +/- 4.0, 11.7 +/- 9.4 and 10.89 +/- 9.0; day 21: total 39.1 +/- 35.3 and 15.4 +/- 16.9, 12.3 +/- 11.4 and 17.3 +/- 16.8 umol, respectively.