A new method of energy prescription to improve weight loss.

Clinical outcome audit was carried out on two groups of obese out-patients for a 3-month follow-up period. In the first audit group of 35 patients (A1), energy intake was prescribed by diet history, whereas in the second audit group of 27 patients (A2) energy intake was prescribed from an estimate of individual energy requirements based on age, sex, and activity. There was no significant difference in age or initial BMI between the two groups and the failure-to-attend rate was the same in each group. Patients in Group A2 received a significantly higher energy prescription (P<0.001) than Group A1, but this was still significantly more restricted than the recommended 500 kcal energy deficit from energy expenditure (P<0.05). Weight loss was significant in both groups, but was greater in Group A2 than in Group A1. There was no significant correlation between weight loss and energy deficit. In a selected group of patients from Group A2 who were prescribed energy intake close to the recommended deficit of 500 kcal, weight loss was found to be significantly greater (P<0.05) when compared to the weight loss in Group A1. Results suggest that a diet prescription with an energy deficit below the estimated energy requirements does not lead to greater weight loss and probably reduces compliance. Estimating individual energy requirements rather than using dietary assessment may improve weight loss.