Introduction and Study Design
Obesity continues to be a growing public health concern in the United States, and classic dietary approaches to weight loss have generally been unsuccessful. Over the past decade, scientists have documented the critical role that dietary protein and certain amino acids play during weight loss. More recently, studies have shown that the amino acid leucine facilitates the weight loss process by sparing lean body mass. These findings prompted the design and testing of a novel weight loss program featuring caloric control, moderately high protein content and additional leucine. We conducted an uncontrolled, 12-week use trial with 27 moderately overweight, but otherwise healthy men and women. Subjects were instructed to consume two beverage shakes, three dietary supplement tablets, one nutrition bar, and a healthy meal and/or snack daily.

Summary of Results
Data from 14 participants shows that subjects lost an average of 15.4 pounds and maintained their fat-free mass based on estimates from skinfold caliper measures. Together, these data suggest that weight loss was derived primarily from body fat and that fat-free mass was preserved. Waist and hip measurements were reduced by 4.1 and 2.6 inches respectively, which was a significant reduction in waist to hip ratio, a predictor of cardiovascular disease. In addition, favorable changes were observed in blood lipids, including a 10% drop in total cholesterol and 34% drop in triglycerides. Additionally, no significant adverse events were noted by participants over the 12 weeks, and there were no significant changes in markers of renal and liver function or blood chemistries.

Conclusions
These findings appear to support recent scientific evidence which suggests that consumption of additional leucine during a weight loss diet spares lean tissue. This trial also demonstrated favorable changes in body circumference and blood lipid measures, which further supports the ability of weight loss to have a positive impact on markers associated with disease. In conclusion, this trial provides preliminary evidence that adherence to a novel weight loss program for 12-weeks resulted in effective weight loss and provides additional scientific support for the role of leucine in sparing lean tissue loss during caloric restriction.

Anthropometrics

Data are presented as ± SEM.  *Indicates P <0.01, † indicates P <0.05.

Blood Lipids