Nutritional Strategy to Minimize Early Lean Mass Loss after SG: The Role of Low-BCAA Soy Peptide Supplements

Sleeve gastrectomy (SG) is an effective bariatric procedure but often results in rapid fat-free mass (FFM) loss during the early postoperative period, which may impair recovery and metabolic stability. This study evaluated the effects of different protein supplements low-BCAA soy peptide-based (LBP), whey protein-based (WP), and compound protein-based (CP) on FFM preservation one month after SG.

A retrospective cohort study was conducted on 200 SG patients categorized by postoperative protein supplementation strategy. Body composition was assessed using bioelectrical impedance analysis before and one month after surgery. Primary outcomes included changes in total and regional FFM, with subgroup analyses based on age, sex, and baseline FFM. Covariate-adjusted comparisons controlled for age, sex, and baseline BMI.

At one month postoperatively, the LBP group demonstrated significantly lower percentage FFM loss from total weight loss (%FFML/WL) and smaller reductions in absolute FFM compared to the CP and WP groups (p < 0.05). These differences remained significant after adjustment. Subgroup analysis indicated greater FFM preservation in female patients, those under 30 years of age, and patients with baseline FFM ≤ 50 kg.

Low-BCAA soy peptide supplementation was associated with superior early FFM preservation after SG, particularly in younger and leaner patients. These findings suggest that LBP may be an effective component of early postoperative nutritional care to minimize muscle loss and highlight the combined importance of adequate protein intake and physical activity in optimizing lean mass preservation.