Glp-1 Weight Loss Is Driven Mainly By Fat Loss, Not Muscle Loss

A systematic reappraisal and meta-analysis finds that GLP-1-based treatments thrust clinically meaningful weight nonaccomplishment chiefly done fat reduction, but experts pass that preserving musculus remains basal for semipermanent metabolic health.

Review: GLP-1 agonists and changes successful assemblage wide and creation successful adults pinch overweight aliases obesity pinch aliases without type 2 glucosuria mellitus: a systematic reappraisal and meta-analysis. Image Credit: Love Employee / Shutterstock

In a caller study published successful the International Journal of Obesity, researchers assessed nan effects of glucagon-like peptide 1 (GLP-1) receptor agonists (RAs) and dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) agonists connected weight and assemblage creation successful adults pinch overweight aliases obesity.

GLP-1 Therapy and Obesity Treatment Background

The prevalence of obesity has markedly accrued worldwide complete nan past decades. Obesity is associated pinch respective cardiometabolic complications, which trim nan value of life arsenic good arsenic life expectancy. As such, effective guidance of obesity requires a personalized, multidisciplinary attack combining behavioral and dietary interventions, pharmacological therapies, beingness activity, and surgery.

GLP-1RAs and related incretin-based therapies lend to sustained weight nonaccomplishment successful obese individuals, which is accompanied by improvements successful related comorbidities. GLP-1RAs person besides shown cardioprotective properties. While these medications chiefly trim fat assemblage wide (FBM), nonaccomplishment of thin assemblage wide (LBM) tin besides occur, raising concerns astir musculus nonaccomplishment successful susceptible populations, specified arsenic frail individuals and older adults.

GLP-1 Body Composition Meta-Analysis Methods

In nan coming study, researchers evaluated the efficacy of GLP-1RAs and dual GLP-1/GIP agonists successful modulating assemblage creation and promoting weight nonaccomplishment successful adults pinch overweight aliases obesity pinch aliases without type 2 glucosuria (T2D). First, Web of Science, PubMed, and Scopus databases were comprehensively searched for objective studies assessing nan effects of GLP-1-based therapies connected anthropometric indices and assemblage creation successful nan specified populations. After deduplication, abstracts/titles and full-texts were assessed for inclusion.

The Study Quality Assessment Tools were utilized to measure methodological quality. Meta-analyses were performed connected eligible studies that presented numerical information connected nan changes successful prime assemblage creation and anthropometric parameters pinch GLP-1-based treatment. Data were pooled utilizing random-effects models, and subgroup analyses were performed by supplier type and curen duration. Publication bias was assessed utilizing Egger’s test.

In total, 36 studies were included successful nan qualitative study and 24 successful nan meta-analyses. Most studies were conducted successful Europe and Asia, and astir reported outcomes aft 6 months of treatment. Twenty-four studies included individuals pinch T2D. Liraglutide and semaglutide were nan astir often investigated GLP-1RAs. The included studies varied successful design, populations, supplier regimens, curen duration, and body-composition methods. Bioelectrical impedance study and dual-energy x-ray absorptiometry were nan astir communal methods to measure assemblage composition.

Weight Loss and Lean Mass Findings

Significant improvements successful assemblage creation and anthropometric parameters were observed aft GLP-1-based treatment. At 3 months, a important 9% simplification successful assemblage wide was observed, particularly successful beinaglutide recipients, pinch marked decreases successful visceral adipose insubstantial (VAT) area (−29.25 cm²) and FBM (−17%). A humble but important LBM nonaccomplishment (−2%) besides occurred. Body wide scale (BMI) and waist circumference (WC) besides decreased by 2.96 kg/m² and 9.6 cm, respectively.

At six months, assemblage wide was importantly decreased by 5%, and some FBM and LBM showed important reductions of 6% and 1%, respectively. BMI decreased by 2.40 kg/m², while WC showed a humble simplification (−2.3 cm). Moreover, a important 3% simplification successful skeletal musculus wide was observed. There was besides a important alteration successful nan VAT area (−32.31 cm²).

At 12 months, assemblage wide decreased by 4%, WC decreased by 3.2 cm, and BMI decreased by 1.74 kg/m². The largest reductions were reported successful a liraglutide study, though nan authors noted important interstudy variability and cautioned against overinterpreting agent-specific differences. Further, FBM and LBM were importantly reduced by 4%. Egger’s trial revealed important publication bias for immoderate outcomes astatine 3 months, pinch nary grounds of bias for astir outcomes astatine different clip points.

Clinical Implications for Fat Loss and Muscle Preservation

Together, nan findings exemplify nan important efficacy of GLP-1-based therapies connected anthropometric indices associated pinch obesity. Body mass, BMI, and WC showed important reductions astatine 3, 6, and 12 months of treatment. The astir important and accelerated changes occurred successful nan first 3 months, particularly pinch beinaglutide successful position of BMI and weight reduction. Specifically, assemblage wide decreased by 9% aft 3 months, 5% aft six months, and 4% aft 12 months.

GLP-1-based therapies led to favorable changes successful assemblage composition, pinch important reductions successful VAT and FBM, peculiarly during nan first six months. While LBM nonaccomplishment was evident, it was comparatively humble compared to assemblage wide loss.

The authors characterized this shape arsenic “quality” weight loss, driven chiefly by fat wide simplification pinch comparative preservation of thin tissue. Notably, nary single GLP-1RA was superior to nan others successful preserving thin mass.

Future studies should research much effective combinations of manner interventions and pharmacotherapy, pinch accent connected maintaining metabolic wellness and preserving thin mass, peculiarly done nutritional support and guidance training, among group astatine higher consequence of sarcopenia.