The efficacy and metabolic effects of two different regimens of very low calorie diet.

Eighteen refractory obese patients received a formula diet of 240 kcal per day using Modifast (VLCD 240) for 1-2 months of patient treatment. Another 22 obese patients were treated by Optifast 70, which supplies 420 kcal per day (VLCD 420), for 1-2 months on an inpatient or outpatient basis. The weight losses attained through these VLCD regimens during the first month of treatment were compared. In addition, the metabolic effects of each VLCD regimen were investigated in 21 inpatients, of whom 11 received the VLCD 240 and 10 received the VLCD 420. The nitrogen balance, levels of serum rapid turnover proteins and serum total ketone bodies concentration of each individual treated by the two different VLCD regimens were also investigated. The VLCD 420 showed an identical weight reduction effect (7.6 +/- 2.4 kg/month) to that attained by the VLCD 240 (8.9 +/- 3.1 kg/month). The nitrogen balance turned out to be negative in each VLCD regimen for the first week of treatment. The VLCD 240 negative nitrogen balance continued to the end of the fourth week, but the VLCD 420 negative nitrogen balance recovered to a state of equilibrium around the third or fourth weeks. The serum prealbumin and retinol-binding protein levels decreased rapidly after the initiation of each VLCD regimen; however, a prominent decrease of the serum retinol-binding protein level was observed with the VLCD 240. A positive correlation between the total nitrogen loss and the decrease of serum prealbumin concentration was observed during the first month of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)