Very low and low-calorie diets ((V)LCD) are commonly used in the early phase of obesity treatment programmes. Recently, a new formula, Allévo^®, was introduced in Scandinavia. No study has hitherto assessed its efficacy compared to the commonly used (V)LCD Nutrilett^®.

To compare Allévo^® with Nutrilett^® regarding short-term effects on weight and BMI loss, ketonaemia, compliance, and body composition.

Thirty-six males (baseline: age 46.5±10.9 year; BMI 39.2±3.8kg/m²; %BF 38.8±3.9%) participated in a randomized trial comparing two LCDs, differing mainly in protein and dietary fibre composition. Body composition was measured by DXA at baseline and end, while body weight was measured weekly during the 8-week (V) LCD-intervention. The main outcome measures were weight, BMI, waist-circumference (WC), and body fat percentage (%BF).

No significant differences between groups in age, weight, blood pressure, or %BF were observed at baseline (all p>0.3). The mean BMI change over the study period was −4.4±0.3 and −4.2±1.9kg/m² for Nutrilett^® and Allévo^®, respectively (p=0.72), while WC was reduced by 9.6±1.0 and 10.1±3.2cm, respectively (p=0.51). About 49% of the weight loss consisted of fat. When examining the weight development during the intervention, with the eight repeated measures, no significant difference in the slope of the weight loss curve could be detected (p=0.50–0.65). Ketonaemia developed similarly in both groups, and did not correlate to weight loss.

Allévo^® and Nutrilett^® appear to have equivalent efficacy regarding weight, BMI, WC, and %BF loss in short-term interventions.