Study highlights new benefits and risks of GLP-1 weight-loss drugs
Researchers at Pennington Biomedical Research Center report additional health effects of GLP-1 medications, including reduced alcohol intake and arthritis relief, while noting concerns such as nutrient deficiencies and muscle loss.
Doctors have been prescribing GLP-1 drugs for obesity for about five years, but a 15-year study by Pennington Biomedical Research Center professor Steven Heymsfield suggests the drugs may have broader impacts. He said some effects were anticipated, such as lower diabetes risk, while others were unexpected.
"People report less desire to drink alcohol," Heymsfield said, noting early studies that support the observation.
Patients with arthritis have reported less pain and inflammation, leading to fewer knee replacements, according to Heymsfield. Cardiovascular benefits have also been documented, with reductions in heart attacks, cardiovascular disease and mortality that appear to involve anti-inflammatory mechanisms beyond weight loss.
The researcher cautioned that off-label use of GLP-1 agents to treat inflammation in individuals of normal weight carries unknown risks. He added that the drugs’ influence on brain pathways may explain the decreased interest in alcohol and other substances, though the exact mechanisms remain unclear.
Adverse effects include inadequate food intake and rare vitamin deficiencies such as scurvy, as well as a loss of pleasure in eating, which some patients describe as “hedonia.” Excessive suppression of appetite cues, termed “food noise,” can also occur. Muscle and bone loss are common among users who lose weight, prompting investigations into higher protein diets, resistance training and adjunctive medications to preserve lean tissue.
Heymsfield highlighted ongoing phase-three trials of retatrutide, a triple-agonist combining GLP-1, GIP and glucagon, which has produced weight reductions of 25-30 %, comparable to bariatric surgery, but with a higher side-effect profile. He said the drug could be approved within the next few years.
Overall, GLP-1 drugs are considered safe when used as directed, with predictable gastrointestinal side effects and low overall risk at lower doses. Their effects cease after discontinuation unless patients maintain lifestyle changes, and weight regain is common and typically involves fat rather than muscle. Future formulations aim for longer dosing intervals and strategies to protect muscle and bone mass.