Weight Loss With Ozempic May Weaken Muscles Even When Size Remains Stable

As usage of nan celebrated anti-diabetic and weight-loss supplier Ozempic skyrockets, truthful person concerns astir nan medication's broadside effects. One specified broadside effect is nonaccomplishment of "lean mass"-body weight that isn't fat-raising concerns that Ozempic could beryllium reducing musculus wide and strength.

New investigation successful mice suggests that musculus wide changes little than expected, but muscles whitethorn still get weaker, pointing retired an urgent request for objective studies to pin down nan afloat effects of nan celebrated medications.

"If we want to really thief nan individuals who whitethorn beryllium losing musculus mass, past we request to cognize that they're really losing musculus mass," says Katsu Funai, PhD, subordinate professor of nutrition and integrative physiology successful nan University of Utah College of Health and nan elder writer connected nan study. "We person information successful mice that propose that things are not arsenic straightforward arsenic they mightiness seem."

The results are published successful Cell Metabolism.

Researchers recovered that Ozempic-induced weight nonaccomplishment did alteration thin wide by astir 10%. Most of this mislaid weight wasn't from skeletal muscles but alternatively from different tissues for illustration nan liver, which shrunk by astir half. The researchers stress that much investigation is needed to find whether akin changes to organ size hap successful humans-and whether those changes travel pinch immoderate risks.

"Loss of wide successful metabolically progressive organs, specified arsenic nan liver, is expected arsenic portion of patient weight loss," says Ran Hee Choi, PhD, investigation coach successful nutrition and integrative physiology astatine U of U Health and co-first writer connected nan study. In some mice and humans, weight summation and nonaccomplishment tin impact nan size of organs for illustration nan liver without affecting their function.

It's improbable that nan observed thin wide nonaccomplishment represents a superior adverse effect."

Takuya Karasawa, PhD, postdoctoral interrogator successful nan U of U Molecular Medicine Program and co-first writer connected nan study

Some skeletal muscles did shrink arsenic nan mice mislaid weight-on average, by astir 6%, not capable to explicate nan wide nonaccomplishment successful thin mass. Other muscles stayed nan aforesaid size.

Some of this nonaccomplishment successful musculus wide is simply a return to baseline, nan researchers say. Gains successful fat besides thin to lead to gains successful skeletal muscle, since nan assemblage must do much activity to move around. So nonaccomplishment of fat tin lead to nonaccomplishment of musculus without affecting wide value of life.

Interestingly, erstwhile nan researchers tested nan magnitude of unit nan mice's muscles could exert, they recovered that, for immoderate muscles, spot decreased arsenic nan mice mislaid weight, moreover erstwhile nan size of nan musculus stayed astir nan same. For different muscles, spot was unchanged. It's chartless really weight nonaccomplishment narcotics impact this equilibrium successful people, nan researchers say.

A imaginable nonaccomplishment of spot erstwhile taking Ozempic whitethorn beryllium of peculiar interest for adults complete nan property of 60, who are astatine higher baseline consequence for musculus nonaccomplishment and reduced mobility. "The nonaccomplishment of beingness usability is simply a beardown predictor of not conscionable value of life but longevity," Funai adds.

The researchers be aware against extrapolating their results straight into humans, because mice and humans summation and suffer weight successful different ways. In people, obesity is associated pinch little beingness activity, but mice don't thin to go little progressive erstwhile they summation weight. And nan mice successful this study became overweight because they ate a high-fat diet, whereas group go overweight for a wide assortment of reasons that see genetics, diet, sleeping patterns, and age.

Instead of drafting a one-to-one parallel pinch humans, nan researchers opportunity their results stress nan request for much objective studies. "There remains a important request for validation successful humans, particularly concerning musculus strength," Karasawa says.

Funai adds that objective tests should cheque for changes successful musculus spot not conscionable for Ozempic but besides early weight-loss drugs. "There are galore further weight nonaccomplishment narcotics that are successful objective tests and coming retired successful nan adjacent 3 to 5 years," Funai says. "But pinch each those objective trials, if they're willing successful measuring thin wide loss, they request to see beingness function."

"Our findings are really interesting, but this is simply a preclinical model," he adds. "We request these information successful people."

The results are published successful Cell Metabolism as "Unexpected effects of semaglutide connected skeletal musculus wide and force-generating capacity successful mice."

This study was supported by nan National Institutes of Health, including nan National Institute of Diabetes and Digestive and Kidney Diseases (grant numbers DK107397 and DK127979), nan National Institute of General Medical Sciences (grant number GM144613), nan National Institute connected Aging (grant numbers AG074535, AG065993, AG076075, and AG086328), and nan National Cancer Institute (grant number CA286584), arsenic good arsenic by nan Grant-in-aid for Japan Society for Promotion of Science Fellows (grant number 24KJ2039). Content is solely nan work of nan authors and does not needfully correspond nan charismatic views of nan National Institutes of Health.